From e496cf68df9ff3f15006a9fbd92759f4bbf11c55 Mon Sep 17 00:00:00 2001
From: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
Date: Fri, 3 Apr 2020 00:16:37 +0000
Subject: [PATCH 01/34] updating DIRECTORY.md

---
 DIRECTORY.md | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/DIRECTORY.md b/DIRECTORY.md
index 7167850a..626c5c63 100644
--- a/DIRECTORY.md
+++ b/DIRECTORY.md
@@ -243,10 +243,10 @@
     * [Sol1](https://github.com/TheAlgorithms/C/blob/master/project_euler/Problem%2015/sol1.c)
   * Problem 16
     * [Sol1](https://github.com/TheAlgorithms/C/blob/master/project_euler/Problem%2016/sol1.c)
-  * Problem 20
-    * [Sol1](https://github.com/TheAlgorithms/C/blob/master/project_euler/Problem%2020/sol1.c)
   * Problem 19
     * [Sol1](https://github.com/TheAlgorithms/C/blob/master/project_euler/Problem%2019/sol1.c)
+  * Problem 20
+    * [Sol1](https://github.com/TheAlgorithms/C/blob/master/project_euler/Problem%2020/sol1.c)
   * Problem 21
     * [Sol1](https://github.com/TheAlgorithms/C/blob/master/project_euler/Problem%2021/sol1.c)
   * Problem 22
@@ -254,6 +254,8 @@
   * Problem 23
     * [Sol1](https://github.com/TheAlgorithms/C/blob/master/project_euler/Problem%2023/sol1.c)
     * [Sol2](https://github.com/TheAlgorithms/C/blob/master/project_euler/Problem%2023/sol2.c)
+  * Problem 25
+    * [Sol1](https://github.com/TheAlgorithms/C/blob/master/project_euler/Problem%2025/sol1.c)
 
 ## Searching
   * [Binary Search](https://github.com/TheAlgorithms/C/blob/master/searching/Binary_Search.c)

From daca8c97e29385c32bcadbc83ca05ff6867c7f18 Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Thu, 2 Apr 2020 23:50:51 -0400
Subject: [PATCH 02/34] brute-force method

---
 project_euler/Problem 26/sol1.c | 74 +++++++++++++++++++++++++++++++++
 1 file changed, 74 insertions(+)
 create mode 100644 project_euler/Problem 26/sol1.c

diff --git a/project_euler/Problem 26/sol1.c b/project_euler/Problem 26/sol1.c
new file mode 100644
index 00000000..bb9d9da8
--- /dev/null
+++ b/project_euler/Problem 26/sol1.c	
@@ -0,0 +1,74 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#ifdef _OPENMP
+#include <omp.h>
+#endif
+
+#define MAX_DENO 2000
+#define MAX_LEN (MAX_DENO + 10)
+
+int compare(const void *a, const void *b)
+{
+    return (*(unsigned short *)a - *(unsigned short *)b);
+}
+
+int main(int argc, char *argv[])
+{
+    unsigned short max_digits = 0, max_idx_number = 0;
+
+    clock_t start_time = clock();
+#ifdef _OPENMP
+#pragma omp for
+#endif
+    for (unsigned short deno = 2; deno < MAX_DENO; deno++)
+    {
+        unsigned short remainders[MAX_LEN];
+        unsigned short rem = 1, *rem_ptr = remainders;
+        memset(remainders, (unsigned short)-1, MAX_LEN * sizeof(unsigned short));
+        // remainders[0] = 1;
+        // printf("1/%-4u\t ", deno);
+        unsigned short index = 0, num_digits;
+
+        while (rem != 0)
+        {
+            rem = (rem * 10) % deno;
+            if (rem == 0)
+            {
+                index = 0;
+                break;
+            }
+            rem_ptr = (unsigned short *)bsearch(&rem, remainders, MAX_LEN, sizeof(unsigned short), compare);
+            // printf("%2d, ", rem);
+            // printf("(%14p), ", rem_ptr);
+            if (rem_ptr != NULL)
+                break;
+            remainders[index] = rem;
+            rem_ptr = remainders;
+            index++;
+        }
+
+        num_digits = index - (rem_ptr - remainders);
+        // printf("\n\t(%14p, %14p, %4u, %4u)\n", rem_ptr, remainders, index, num_digits);
+#ifdef _OPENMP
+#pragma omp critical
+        {
+#endif
+            if (num_digits > max_digits)
+            {
+                max_digits = num_digits;
+                max_idx_number = deno;
+                // printf("\t (%u, %u)\n ", max_digits, max_idx_number);
+            }
+#ifdef _OPENMP
+        }
+#endif
+    }
+    clock_t end_time = clock();
+
+    printf("Time taken: %.4g ms\n", 1e3 * (double)(end_time - start_time) / CLOCKS_PER_SEC);
+    printf("Maximum digits: %hu\t Denominator: %hu\n", max_digits, max_idx_number);
+
+    return 0;
+}

From b12e387bce93ffdf66c955a4351659a0216ee38f Mon Sep 17 00:00:00 2001
From: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
Date: Fri, 3 Apr 2020 03:51:13 +0000
Subject: [PATCH 03/34] updating DIRECTORY.md

---
 DIRECTORY.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/DIRECTORY.md b/DIRECTORY.md
index 626c5c63..e67ff0b1 100644
--- a/DIRECTORY.md
+++ b/DIRECTORY.md
@@ -256,6 +256,8 @@
     * [Sol2](https://github.com/TheAlgorithms/C/blob/master/project_euler/Problem%2023/sol2.c)
   * Problem 25
     * [Sol1](https://github.com/TheAlgorithms/C/blob/master/project_euler/Problem%2025/sol1.c)
+  * Problem 26
+    * [Sol1](https://github.com/TheAlgorithms/C/blob/master/project_euler/Problem%2026/sol1.c)
 
 ## Searching
   * [Binary Search](https://github.com/TheAlgorithms/C/blob/master/searching/Binary_Search.c)

From 855c9124b8ed936f46191a176845616a5e6a3dc6 Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Fri, 3 Apr 2020 08:10:28 -0400
Subject: [PATCH 04/34] added stdint.h for integer length typedefs

---
 hash/test_program.c             |  40 +++---
 project_euler/Problem 25/sol1.c |   1 +
 sorting/shell_Sort.c            | 222 ++++++++++++++++----------------
 3 files changed, 132 insertions(+), 131 deletions(-)

diff --git a/hash/test_program.c b/hash/test_program.c
index 3f741bc6..1ce85c85 100644
--- a/hash/test_program.c
+++ b/hash/test_program.c
@@ -1,20 +1,20 @@
-/*
-    author: Christian Bender
-    This file contains a simple test program for each hash-function.
-*/
-
-#include <stdio.h>
-#include "hash.h"
-
-int main(void)
-{
-    char s[] = "hello";
-
-    /* actual tests */
-    printf("sdbm: %s --> %llX\n", s, sdbm(s));
-    printf("djb2: %s --> %llX\n", s, djb2(s));
-    printf("xor8: %s --> %X\n", s, xor8(s)); /* 8 bit */
-    printf("adler_32: %s --> %X\n", s, adler_32(s)); /* 32 bit */
-
-    return 0;
-}
+/*
+    author: Christian Bender
+    This file contains a simple test program for each hash-function.
+*/
+
+#include <stdio.h>
+#include "hash.h"
+
+int main(void)
+{
+    char s[] = "hello";
+
+    /* actual tests */
+    printf("sdbm: %s --> %llX\n", s, sdbm(s));
+    printf("djb2: %s --> %llX\n", s, djb2(s));
+    printf("xor8: %s --> %X\n", s, xor8(s)); /* 8 bit */
+    printf("adler_32: %s --> %X\n", s, adler_32(s)); /* 32 bit */
+
+    return 0;
+}
diff --git a/project_euler/Problem 25/sol1.c b/project_euler/Problem 25/sol1.c
index b6addd95..db96af96 100644
--- a/project_euler/Problem 25/sol1.c	
+++ b/project_euler/Problem 25/sol1.c	
@@ -1,5 +1,6 @@
 #include <stdio.h>
 #include <string.h>
+#include <stdint.h>
 #include <stdlib.h>
 #include <time.h>
 
diff --git a/sorting/shell_Sort.c b/sorting/shell_Sort.c
index 8ebf6fcc..f40716ac 100644
--- a/sorting/shell_Sort.c
+++ b/sorting/shell_Sort.c
@@ -1,111 +1,111 @@
-#include <stdio.h>
-#include <stdlib.h>
-#include <time.h>
-
-#define ELEMENT_NR 20000
-#define ARRAY_LEN(x) (sizeof(x) / sizeof((x)[0]))
-const char *notation = "Shell Sort Big O Notation:\
-						\n--> Best Case: O(n log(n)) \
-						\n--> Average Case: depends on gap sequence \
-						\n--> Worst Case: O(n)";
-
-void show_data(int arr[], int len)
-{
-    int i;
-
-    for (i = 0; i < len; i++)
-        printf("%3d ", arr[i]);
-    printf("\n");
-}
-
-void swap(int *a, int *b)
-{
-    int tmp;
-
-    tmp = *a;
-    *a = *b;
-    *b = tmp;
-}
-
-void shellSort(int array[], int len)
-{
-    int i, j, gap;
-
-    for (gap = len / 2; gap > 0; gap = gap / 2)
-        for (i = gap; i < len; i++)
-            for (j = i - gap; j >= 0 && array[j] > array[j + gap]; j = j - gap)
-                swap(&array[j], &array[j + gap]);
-}
-
-/**
- * Optimized algorithm - takes half the time as other
- **/
-void shell_sort2(int array[], int LEN)
-{
-    const int gaps[] = {701, 301, 132, 57, 23, 10, 4, 1};
-    const int gap_len = 8;
-    int i, j, g;
-
-    for (g = 0; g < gap_len; g++)
-    {
-        int gap = gaps[g];
-        for (i = gap; i < LEN; i++)
-        {
-            int tmp = array[i];
-
-            for (j = i; j >= gap && (array[j - gap] - tmp) > 0; j -= gap)
-                array[j] = array[j - gap];
-            array[j] = tmp;
-        }
-    }
-#ifdef DEBUG
-    for (i = 0; i < LEN; i++)
-        printf("%s\t", data[i]);
-#endif
-}
-
-int main(int argc, char *argv[])
-{
-    int i;
-    int array[ELEMENT_NR];
-    int array2[ELEMENT_NR];
-    int range = 500;
-    int size;
-    clock_t start, end;
-    double time_spent;
-
-    srand(time(NULL));
-    for (i = 0; i < ELEMENT_NR; i++)
-    {
-        array[i] = rand() % range + 1;
-        array2[i] = array[i];
-    }
-
-    size = ARRAY_LEN(array);
-
-    show_data(array, size);
-    start = clock();
-    shellSort(array, size);
-    end = clock();
-    time_spent = (double)(end - start) / CLOCKS_PER_SEC;
-
-    printf("Data Sorted\n");
-    show_data(array, size);
-
-    printf("%s\n", notation);
-    printf("Time spent sorting: %.4g ms\n", time_spent * 1e3);
-
-    printf("--------------------------\n");
-    start = clock();
-    shell_sort2(array2, size);
-    end = clock();
-    time_spent = (double)(end - start) / CLOCKS_PER_SEC;
-
-    printf("Data Sorted\n");
-    show_data(array2, size);
-
-    printf("%s\n", notation);
-    printf("Time spent sorting: %.4g ms\n", time_spent * 1e3);
-
-    return 0;
-}
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+
+#define ELEMENT_NR 20000
+#define ARRAY_LEN(x) (sizeof(x) / sizeof((x)[0]))
+const char *notation = "Shell Sort Big O Notation:\
+						\n--> Best Case: O(n log(n)) \
+						\n--> Average Case: depends on gap sequence \
+						\n--> Worst Case: O(n)";
+
+void show_data(int arr[], int len)
+{
+    int i;
+
+    for (i = 0; i < len; i++)
+        printf("%3d ", arr[i]);
+    printf("\n");
+}
+
+void swap(int *a, int *b)
+{
+    int tmp;
+
+    tmp = *a;
+    *a = *b;
+    *b = tmp;
+}
+
+void shellSort(int array[], int len)
+{
+    int i, j, gap;
+
+    for (gap = len / 2; gap > 0; gap = gap / 2)
+        for (i = gap; i < len; i++)
+            for (j = i - gap; j >= 0 && array[j] > array[j + gap]; j = j - gap)
+                swap(&array[j], &array[j + gap]);
+}
+
+/**
+ * Optimized algorithm - takes half the time as other
+ **/
+void shell_sort2(int array[], int LEN)
+{
+    const int gaps[] = {701, 301, 132, 57, 23, 10, 4, 1};
+    const int gap_len = 8;
+    int i, j, g;
+
+    for (g = 0; g < gap_len; g++)
+    {
+        int gap = gaps[g];
+        for (i = gap; i < LEN; i++)
+        {
+            int tmp = array[i];
+
+            for (j = i; j >= gap && (array[j - gap] - tmp) > 0; j -= gap)
+                array[j] = array[j - gap];
+            array[j] = tmp;
+        }
+    }
+#ifdef DEBUG
+    for (i = 0; i < LEN; i++)
+        printf("%s\t", data[i]);
+#endif
+}
+
+int main(int argc, char *argv[])
+{
+    int i;
+    int array[ELEMENT_NR];
+    int array2[ELEMENT_NR];
+    int range = 500;
+    int size;
+    clock_t start, end;
+    double time_spent;
+
+    srand(time(NULL));
+    for (i = 0; i < ELEMENT_NR; i++)
+    {
+        array[i] = rand() % range + 1;
+        array2[i] = array[i];
+    }
+
+    size = ARRAY_LEN(array);
+
+    show_data(array, size);
+    start = clock();
+    shellSort(array, size);
+    end = clock();
+    time_spent = (double)(end - start) / CLOCKS_PER_SEC;
+
+    printf("Data Sorted\n");
+    show_data(array, size);
+
+    printf("%s\n", notation);
+    printf("Time spent sorting: %.4g ms\n", time_spent * 1e3);
+
+    printf("--------------------------\n");
+    start = clock();
+    shell_sort2(array2, size);
+    end = clock();
+    time_spent = (double)(end - start) / CLOCKS_PER_SEC;
+
+    printf("Data Sorted\n");
+    show_data(array2, size);
+
+    printf("%s\n", notation);
+    printf("Time spent sorting: %.4g ms\n", time_spent * 1e3);
+
+    return 0;
+}

From c4c2263cc6a34eb79a3b3a871e58d92d97c0cc9f Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Tue, 7 Apr 2020 09:36:29 -0400
Subject: [PATCH 05/34] ignore build folder

---
 .gitignore | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.gitignore b/.gitignore
index 8d3f5c3f..2f208ece 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,3 +2,4 @@
 *.exe
 *.out
 .vscode/
+build

From 17419855cbd9ce9c421ae9a0b0c85890cc295d9f Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Tue, 7 Apr 2020 12:22:31 -0400
Subject: [PATCH 06/34] revert to single function implementation of shell_sort

---
 sorting/shell_Sort.c | 43 -------------------------------------------
 1 file changed, 43 deletions(-)

diff --git a/sorting/shell_Sort.c b/sorting/shell_Sort.c
index f40716ac..d9e7a304 100644
--- a/sorting/shell_Sort.c
+++ b/sorting/shell_Sort.c
@@ -37,38 +37,10 @@ void shellSort(int array[], int len)
                 swap(&array[j], &array[j + gap]);
 }
 
-/**
- * Optimized algorithm - takes half the time as other
- **/
-void shell_sort2(int array[], int LEN)
-{
-    const int gaps[] = {701, 301, 132, 57, 23, 10, 4, 1};
-    const int gap_len = 8;
-    int i, j, g;
-
-    for (g = 0; g < gap_len; g++)
-    {
-        int gap = gaps[g];
-        for (i = gap; i < LEN; i++)
-        {
-            int tmp = array[i];
-
-            for (j = i; j >= gap && (array[j - gap] - tmp) > 0; j -= gap)
-                array[j] = array[j - gap];
-            array[j] = tmp;
-        }
-    }
-#ifdef DEBUG
-    for (i = 0; i < LEN; i++)
-        printf("%s\t", data[i]);
-#endif
-}
-
 int main(int argc, char *argv[])
 {
     int i;
     int array[ELEMENT_NR];
-    int array2[ELEMENT_NR];
     int range = 500;
     int size;
     clock_t start, end;
@@ -76,10 +48,7 @@ int main(int argc, char *argv[])
 
     srand(time(NULL));
     for (i = 0; i < ELEMENT_NR; i++)
-    {
         array[i] = rand() % range + 1;
-        array2[i] = array[i];
-    }
 
     size = ARRAY_LEN(array);
 
@@ -95,17 +64,5 @@ int main(int argc, char *argv[])
     printf("%s\n", notation);
     printf("Time spent sorting: %.4g ms\n", time_spent * 1e3);
 
-    printf("--------------------------\n");
-    start = clock();
-    shell_sort2(array2, size);
-    end = clock();
-    time_spent = (double)(end - start) / CLOCKS_PER_SEC;
-
-    printf("Data Sorted\n");
-    show_data(array2, size);
-
-    printf("%s\n", notation);
-    printf("Time spent sorting: %.4g ms\n", time_spent * 1e3);
-
     return 0;
 }

From 8a895b365a6e0dd36253553ce1dc0a66da82b529 Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Tue, 7 Apr 2020 12:38:22 -0400
Subject: [PATCH 07/34] added new faster implementation for shell-sort

---
 sorting/shell_Sort2.c | 81 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 81 insertions(+)
 create mode 100644 sorting/shell_Sort2.c

diff --git a/sorting/shell_Sort2.c b/sorting/shell_Sort2.c
new file mode 100644
index 00000000..3aeab0d9
--- /dev/null
+++ b/sorting/shell_Sort2.c
@@ -0,0 +1,81 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include "function_timer.h"
+
+#define ELEMENT_NR 20000
+#define ARRAY_LEN(x) (sizeof(x) / sizeof((x)[0]))
+
+void show_data(int arr[], int len)
+{
+    int i;
+
+    for (i = 0; i < len; i++)
+        printf("%3d ", arr[i]);
+    printf("\n");
+}
+
+void swap(int *a, int *b)
+{
+    int tmp;
+
+    tmp = *a;
+    *a = *b;
+    *b = tmp;
+}
+
+/**
+ * Optimized algorithm - takes half the time as other
+ **/
+void shell_sort(int array[], int LEN)
+{
+    const int gaps[] = {701, 301, 132, 57, 23, 10, 4, 1};
+    const int gap_len = 8;
+    int i, j, g;
+
+    for (g = 0; g < gap_len; g++)
+    {
+        int gap = gaps[g];
+        for (i = gap; i < LEN; i++)
+        {
+            int tmp = array[i];
+
+            for (j = i; j >= gap && (array[j - gap] - tmp) > 0; j -= gap)
+                array[j] = array[j - gap];
+            array[j] = tmp;
+        }
+    }
+#ifdef DEBUG
+    for (i = 0; i < LEN; i++)
+        printf("%s\t", data[i]);
+#endif
+}
+
+int main(int argc, char *argv[])
+{
+    int i;
+    int array[ELEMENT_NR];
+    int range = 500;
+    int size;
+    double time_spent;
+
+    srand(time(NULL));
+    for (i = 0; i < ELEMENT_NR; i++)
+        array[i] = rand() % range + 1;
+
+    size = ARRAY_LEN(array);
+
+    function_timer *timer = new_timer();
+
+    show_data(array, size);
+    start_timer(timer);
+    shell_sort(array, size);
+    time_spent = end_timer(timer);
+
+    printf("Data Sorted\n");
+    show_data(array, size);
+
+    printf("Time spent sorting: %.4g s\n", time_spent);
+
+    return 0;
+}

From b0689d9d7a8741f7cc71e49bd068f90957f0843e Mon Sep 17 00:00:00 2001
From: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
Date: Tue, 7 Apr 2020 16:39:21 +0000
Subject: [PATCH 08/34] updating DIRECTORY.md

---
 DIRECTORY.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/DIRECTORY.md b/DIRECTORY.md
index f1e8e3f6..6a44e327 100644
--- a/DIRECTORY.md
+++ b/DIRECTORY.md
@@ -298,4 +298,5 @@
   * [Selection Sort](https://github.com/TheAlgorithms/C/blob/master/sorting/Selection_Sort.c)
   * [Shaker Sort](https://github.com/TheAlgorithms/C/blob/master/sorting/shaker_sort.c)
   * [Shell Sort](https://github.com/TheAlgorithms/C/blob/master/sorting/shell_Sort.c)
+  * [Shell Sort2](https://github.com/TheAlgorithms/C/blob/master/sorting/shell_Sort2.c)
   * [Stooge Sort](https://github.com/TheAlgorithms/C/blob/master/sorting/Stooge_Sort.c)

From 68bf72ef8d8d7539c18ee11c55525df0ce1a876e Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Tue, 7 Apr 2020 18:08:42 -0400
Subject: [PATCH 09/34] updated submodule commit

---
 function_timer | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/function_timer b/function_timer
index 327ddab3..e0dc782b 160000
--- a/function_timer
+++ b/function_timer
@@ -1 +1 @@
-Subproject commit 327ddab3e895c26026eeb39ed7e0b44d82597137
+Subproject commit e0dc782b7b0f162299d10d94b0132f111d89c22f

From 3b576fec20e38ac3fdc61003d4bbc0ea6fb73bd1 Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Tue, 7 Apr 2020 18:11:24 -0400
Subject: [PATCH 10/34] added sorting folder to cmake

---
 CMakeLists.txt         |  1 +
 sorting/CMakeLists.txt | 23 +++++++++++++++++++++++
 2 files changed, 24 insertions(+)
 create mode 100644 sorting/CMakeLists.txt

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6c8b0795..438e4439 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -16,6 +16,7 @@ include_directories(function_timer/include)
 add_subdirectory(conversions)
 add_subdirectory(misc)
 add_subdirectory(project_euler)
+add_subdirectory(sorting)
 
 if(USE_OPENMP)
     find_package(OpenMP)
diff --git a/sorting/CMakeLists.txt b/sorting/CMakeLists.txt
new file mode 100644
index 00000000..7033d577
--- /dev/null
+++ b/sorting/CMakeLists.txt
@@ -0,0 +1,23 @@
+if(USE_OPENMP)
+    find_package(OpenMP)
+endif()
+
+# If necessary, use the RELATIVE flag, otherwise each source file may be listed
+# with full pathname. RELATIVE may makes it easier to extract an executable name
+# automatically.
+file( GLOB APP_SOURCES RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} *.c )
+# file( GLOB APP_SOURCES ${CMAKE_SOURCE_DIR}/*.c )
+# AUX_SOURCE_DIRECTORY(${CMAKE_CURRENT_SOURCE_DIR} APP_SOURCES)
+foreach( testsourcefile ${APP_SOURCES} )
+    # I used a simple string replace, to cut off .cpp.
+    string( REPLACE ".c" "" testname ${testsourcefile} )
+    add_executable( ${testname} ${testsourcefile} )
+    # Make sure YourLib is linked to each app
+    target_link_libraries( ${testname} function_timer )
+    set_target_properties(${testname} PROPERTIES LINKER_LANGUAGE C)
+    if(OpenMP_C_FOUND)
+        target_link_libraries(${testname} OpenMP::OpenMP_C)
+    endif()
+    install(TARGETS ${testname} DESTINATION "bin/sorting")
+
+endforeach( testsourcefile ${APP_SOURCES} )

From a3989bbadc645690373f5e7601dcd7d184e204bf Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Tue, 7 Apr 2020 18:21:27 -0400
Subject: [PATCH 11/34] use openmp in 'misc' directory

---
 misc/CMakeLists.txt | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/misc/CMakeLists.txt b/misc/CMakeLists.txt
index be8a549f..493bc06e 100644
--- a/misc/CMakeLists.txt
+++ b/misc/CMakeLists.txt
@@ -1,3 +1,8 @@
+
+if(USE_OPENMP)
+    find_package(OpenMP)
+endif()
+
 # If necessary, use the RELATIVE flag, otherwise each source file may be listed
 # with full pathname. RELATIVE may makes it easier to extract an executable name
 # automatically.
@@ -11,6 +16,9 @@ foreach( testsourcefile ${APP_SOURCES} )
     # Make sure YourLib is linked to each app
     target_link_libraries( ${testname} function_timer )
     set_target_properties(${testname} PROPERTIES LINKER_LANGUAGE C)
+    if(OpenMP_C_FOUND)
+        target_link_libraries(${testname} OpenMP::OpenMP_C)
+    endif()
     install(TARGETS ${testname} DESTINATION "bin/misc")
 
 endforeach( testsourcefile ${APP_SOURCES} )

From cee24685064a4ad3d91682f20122c224c3ba334c Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Tue, 7 Apr 2020 18:29:24 -0400
Subject: [PATCH 12/34] code cleanup & fixed syntax error

---
 sorting/Bubble_Sort_2.c | 57 +++++++++++++++++------------------------
 1 file changed, 24 insertions(+), 33 deletions(-)

diff --git a/sorting/Bubble_Sort_2.c b/sorting/Bubble_Sort_2.c
index f11fd63e..c141ba91 100644
--- a/sorting/Bubble_Sort_2.c
+++ b/sorting/Bubble_Sort_2.c
@@ -1,56 +1,47 @@
 #include <stdio.h>
 #include <stdlib.h>
-#define MAX 20 
+#define MAX 20
 #define TRUE 1
 #define FALSE 0
 
-
 int main()
 {
 
-    int i , arraySort[MAX] ={0} ,  isSort = FALSE, changePlace;
-    
-    
-    /* For example 
+    int i, arraySort[MAX] = {0}, isSort = FALSE, changePlace;
+
+    /* For example
     Insertion random values in array to test
     */
-    
-    
-    for(i = 0 ; i < MAX; i++)
+
+    for (i = 0; i < MAX; i++)
     {
-        arraySort[i] = rand()%101 ;
+        arraySort[i] = rand() % 101;
     }
-    
 
-/* Algorithm of bubble methods */
-    
-    while(isSort)
+    /* Algorithm of bubble methods */
+
+    while (isSort)
     {
-         isSort = FALSE;
+        isSort = FALSE;
 
-         for( i = 0 ; i < MAX - 1 ; i++)
-         {
-              if(arraySort[i] > arraySort[i+1])
-              {
-                 changePlace = arratSort[i];
-                 arraySort[i] = arraySort[i+1];
-                 arraySort[i+1] = changePlace ;
-                 isSort = TRUE;
-              }
-         
-         }
+        for (i = 0; i < MAX - 1; i++)
+        {
+            if (arraySort[i] > arraySort[i + 1])
+            {
+                changePlace = arraySort[i];
+                arraySort[i] = arraySort[i + 1];
+                arraySort[i + 1] = changePlace;
+                isSort = TRUE;
+            }
+        }
     }
 
     /* See if it works */
-    
-    for(i = 0 ; i < MAX; i++)
+
+    for (i = 0; i < MAX; i++)
     {
-       printf("%d\n", arraySort[i]);
+        printf("%d\n", arraySort[i]);
     }
 
-
-
-
     return EXIT_SUCCESS;
-
 }

From dc5d25690b0bd089d0f1fe1d2d2a6b88d2a09de5 Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Tue, 7 Apr 2020 18:33:49 -0400
Subject: [PATCH 13/34] renamed conflicting `mergesort` function

---
 sorting/merge_sort.c | 143 ++++++++++++++++++++++---------------------
 1 file changed, 72 insertions(+), 71 deletions(-)

diff --git a/sorting/merge_sort.c b/sorting/merge_sort.c
index 6533713f..ea2bfba3 100644
--- a/sorting/merge_sort.c
+++ b/sorting/merge_sort.c
@@ -1,91 +1,92 @@
 #include <stdio.h>
+#include <stdlib.h>
 
-void swap (int *a,int *b)//To swap the variables//
+void swap(int *a, int *b) //To swap the variables//
 {
     int t;
-    t= *a;
-    *a=*b;
-    *b=t;
-    
+    t = *a;
+    *a = *b;
+    *b = t;
 }
 
-void merge(int a[],int l,int r,int n)//To merge //
-{  int *b = (int*)malloc(n*sizeof(int));
-int c=l;
-    int p1,p2;
-    p1 = l;p2=((l+r)/2)+1;
-    while ((p1<((l+r)/2)+1) &&(p2<r+1))
-    { if(a[p1] <= a[p2])
-{          b[c++] = a[p1];
-           p1++;
-}
-          else
-          {b[c++] = a[p2];p2++;}
-        
-    };
-    
-    if (p2 == r+1)
+void merge(int a[], int l, int r, int n) //To merge //
+{
+    int *b = (int *)malloc(n * sizeof(int));
+    int c = l;
+    int p1, p2;
+    p1 = l;
+    p2 = ((l + r) / 2) + 1;
+    while ((p1 < ((l + r) / 2) + 1) && (p2 < r + 1))
     {
-       while ((p1<((l+r)/2)+1))
-    { 
-          b[c++] = a[p1];
+        if (a[p1] <= a[p2])
+        {
+            b[c++] = a[p1];
             p1++;
-    }; 
-        
+        }
+        else
+        {
+            b[c++] = a[p2];
+            p2++;
+        }
+    };
+
+    if (p2 == r + 1)
+    {
+        while ((p1 < ((l + r) / 2) + 1))
+        {
+            b[c++] = a[p1];
+            p1++;
+        };
     }
     else
     {
-          while ((p2<r+1))
-    { 
-          b[c++] = a[p2];
-p2++;
-    }; 
-         }
-         
-        for (c=l;c<r-l+1;c++)
+        while ((p2 < r + 1))
+        {
+            b[c++] = a[p2];
+            p2++;
+        };
+    }
+
+    for (c = l; c < r - l + 1; c++)
         a[c] = b[c];
-    
 }
-void mergesort(int a[],int n,int l,int r)
+
+void merge_sort(int *a, int n, int l, int r)
 {
-    if (r-l == 1 )
+    if (r - l == 1)
+    {
+        if (a[l] > a[r])
+            swap(&a[l], &a[r]);
+    }
+    else if (l == r)
     {
-        if (a[l]>a[r])
-        swap(&a[l],&a[r]);
-        
     }
-    else if(l==r)
-    {}
     else
-    {mergesort(a,n,l,(l+r)/2);
-     mergesort(a,n,((l+r)/2)+1,r);
-       merge(a,l,r,n);
-        
+    {
+        merge_sort(a, n, l, (l + r) / 2);
+        merge_sort(a, n, ((l + r) / 2) + 1, r);
+        merge(a, l, r, n);
     }
-    
 }
-int main(void) {   //main function//
-int *a,n,i;
-scanf("%d",&n);
-a = (int*)malloc(n*sizeof(int));
-for (i=0;i<n;i++)
-{
-    
-    scanf("%d",&a[i]);
-    
+int main(void)
+{ //main function//
+    int *a, n, i;
+    scanf("%d", &n);
+    a = (int *)malloc(n * sizeof(int));
+    for (i = 0; i < n; i++)
+    {
+
+        scanf("%d", &a[i]);
+    }
+
+    merge_sort(a, n, 0, n - 1);
+    for (i = 0; i < n; i++)
+    {
+
+        printf(" %d", a[i]);
+    }
+
+    free(a);
+
+    return 0;
 }
-
-mergesort(a,n,0,n-1);
-for (i=0;i<n;i++)
-{
-    
-    printf(" %d",&a[i]);
-    
-}
-
-
-	return 0;
-}
-
-
-

From f23ec833b954c8a490a4f7ba672b3cb588656a62 Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Tue, 7 Apr 2020 18:37:47 -0400
Subject: [PATCH 14/34] code clean + added missing function + syntax
 corrections

---
 sorting/radix_sort_2.c | 119 ++++++++++++++++++++++-------------------
 1 file changed, 64 insertions(+), 55 deletions(-)

diff --git a/sorting/radix_sort_2.c b/sorting/radix_sort_2.c
index 6f0aa062..27428276 100644
--- a/sorting/radix_sort_2.c
+++ b/sorting/radix_sort_2.c
@@ -1,42 +1,44 @@
 //sorting of array list using Radix sort
 #include <stdio.h>
 
-#define range 10  // Range for integers is 10 as digits range from 0-9
+#define range 10 // Range for integers is 10 as digits range from 0-9
 
 // Utility function to get the maximum value in ar[]
-int MAX(int ar[], int size){
-    int i, max = ar[0];
-    for(i = 0; i<size; i++){
-        if(ar[i]>max)
-            max = ar[i];
-    }
-    return max;
+int MAX(int ar[], int size)
+{
+        int i, max = ar[0];
+        for (i = 0; i < size; i++)
+        {
+                if (ar[i] > max)
+                        max = ar[i];
+        }
+        return max;
 }
 
 // Counting sort according to the digit represented by place
-void countSort(int arr[],int n,int place)
+void countSort(int arr[], int n, int place)
 {
-        int i,freq[range]={0};         
+        int i, freq[range] = {0};
         int output[n];
-    
+
         // Store count of occurences in freq[]
-        for(i=0;i<n;i++)
-                freq[(arr[i]/place)%range]++;
-    
+        for (i = 0; i < n; i++)
+                freq[(arr[i] / place) % range]++;
+
         // Change freq[i] so that it contains the actual position of the digit in output[]
-        for(i=1;i<range;i++)
-                freq[i]+=freq[i-1];
-    
+        for (i = 1; i < range; i++)
+                freq[i] += freq[i - 1];
+
         // Build the output array
-        for(i=n-1;i>=0;i--)
+        for (i = n - 1; i >= 0; i--)
         {
-                output[freq[(arr[i]/place)%range]-1]=arr[i];
-                freq[(arr[i]/place)%range]--;
+                output[freq[(arr[i] / place) % range] - 1] = arr[i];
+                freq[(arr[i] / place) % range]--;
         }
-        
+
         // Copy the output array to arr[], so it contains numbers according to the current digit
-        for(i=0;i<n;i++)
-                arr[i]=output[i];
+        for (i = 0; i < n; i++)
+                arr[i] = output[i];
 }
 
 /*This is where the sorting of the array takes place
@@ -44,41 +46,48 @@ void countSort(int arr[],int n,int place)
  n --- Array Size
  max --- Maximum element in Array
  */
-void radixsort(int arr[],int n,int max)            //max is the maximum element in the array
+void radixsort(int arr[], int n, int max) //max is the maximum element in the array
 {
-        int mul=1;
-        while(max)
+        int mul = 1;
+        while (max)
         {
-                countsort(arr,n,mul);
-                mul*=10;
-                max/=10;
+                countSort(arr, n, mul);
+                mul *= 10;
+                max /= 10;
         }
 }
 
-int main(int argc, const char * argv[]){
-    int n;
-    printf("Enter size of array:\n");
-    scanf("%d", &n); // E.g. 8
-    
-    printf("Enter the elements of the array\n");
-    int i;
-    int arr[n];
-    for(i = 0; i < n; i++){
-        scanf("%d", &arr[i] );
-    }
-    
-    printf("Original array: ");
-    display(arr, n);                   // Original array : 10 11 9 8 4 7 3 8
-    
-    int max;
-    max = MAX(arr,n);
-    
-    radixsort(arr, n, max);
-    
-    printf("Sorted array: ");
-    display(arr, n);                // Sorted array : 3 4 7 8 8 9 10 11
-    
-    return 0;
-
-
+void display(int *arr, int N)
+{
+        for (int i = 0; i < N; i++)
+                printf("%d, ", arr[i]);
+        putchar('\n');
+}
+
+int main(int argc, const char *argv[])
+{
+        int n;
+        printf("Enter size of array:\n");
+        scanf("%d", &n); // E.g. 8
+
+        printf("Enter the elements of the array\n");
+        int i;
+        int arr[n];
+        for (i = 0; i < n; i++)
+        {
+                scanf("%d", &arr[i]);
+        }
+
+        printf("Original array: ");
+        display(arr, n); // Original array : 10 11 9 8 4 7 3 8
+
+        int max;
+        max = MAX(arr, n);
+
+        radixsort(arr, n, max);
+
+        printf("Sorted array: ");
+        display(arr, n); // Sorted array : 3 4 7 8 8 9 10 11
+
+        return 0;
 }

From 4138003b540c7aef12913f1a94ba71636d5f7eee Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Tue, 7 Apr 2020 19:08:35 -0400
Subject: [PATCH 15/34] code cleanup + random set of arrays

---
 sorting/Pancake_Sort.c | 33 ++++++++++++++++++---------------
 1 file changed, 18 insertions(+), 15 deletions(-)

diff --git a/sorting/Pancake_Sort.c b/sorting/Pancake_Sort.c
index 4869d3b5..96271704 100644
--- a/sorting/Pancake_Sort.c
+++ b/sorting/Pancake_Sort.c
@@ -24,13 +24,13 @@ int findMax(int arr[], int n)
 
     for (maxElementIdx = 0, i = 0; i < n; ++i)
         if (arr[i] > arr[maxElementIdx])
-                maxElementIdx = i;
+            maxElementIdx = i;
 
     return maxElementIdx;
 }
 
 // Sorts the array using flip operations
-int pancakeSort(int *arr, int n)
+void pancakeSort(int *arr, int n)
 {
     // Start from the complete array and one by one reduce current size by one
     for (int curr_size = n; curr_size > 1; --curr_size)
@@ -39,13 +39,13 @@ int pancakeSort(int *arr, int n)
         int maxElementIdx = findMax(arr, curr_size);
 
         // Move the maximum element to end of current array if it's not already at the end
-        if (maxElementIdx != curr_size-1)
-        { 
+        if (maxElementIdx != curr_size - 1)
+        {
             // To move at the end, first move maximum number to beginning
-            flip(arr, maxElementIdx); 
+            flip(arr, maxElementIdx);
 
             // Now move the maximum number to end by reversing current array
-            flip(arr, curr_size-1); 
+            flip(arr, curr_size - 1);
         }
     }
 }
@@ -53,26 +53,29 @@ int pancakeSort(int *arr, int n)
 // Displays the array, passed to this method
 void display(int arr[], int n)
 {
-    for(int i = 0; i < n; i++)
+    for (int i = 0; i < n; i++)
     {
         printf("%d ", arr[i]);
     }
 
     printf("\n");
-} 
+}
+
+#define N 50
 
 // Driver program to test above function
 int main()
-{ 
-    int arr[] = {23, 10, 20, 11, 12, 6, 7};
-    int n = sizeof(arr)/sizeof(arr[0]); 
+{
+    int arr[N];
+    for (int i = 0; i < N; i++)
+        arr[i] = rand() % (N << 1); /* random numbers from 0 to 2N */
 
     printf("Original array: ");
-    display(arr, n);
+    display(arr, N);
 
-    pancakeSort(arr, n);
+    pancakeSort(arr, N);
     printf("Sorted array: ");
-    display(arr, n);
+    display(arr, N);
 
     return 0;
-} 
\ No newline at end of file
+}
\ No newline at end of file

From 621de22fff75d8c9113858c27d40a37bdb8ab486 Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Tue, 7 Apr 2020 19:28:29 -0400
Subject: [PATCH 16/34] fixed filename - remove apostrophe

---
 .../{simpson's 1-3rd rule.c => simpsons_1-3rd rule.c}             | 0
 1 file changed, 0 insertions(+), 0 deletions(-)
 rename computer_oriented_statistical_methods/{simpson's 1-3rd rule.c => simpsons_1-3rd rule.c} (100%)

diff --git a/computer_oriented_statistical_methods/simpson's 1-3rd rule.c b/computer_oriented_statistical_methods/simpsons_1-3rd rule.c
similarity index 100%
rename from computer_oriented_statistical_methods/simpson's 1-3rd rule.c
rename to computer_oriented_statistical_methods/simpsons_1-3rd rule.c

From e0a78dfa4cee76bdfe57801434316bc270fb4048 Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Tue, 7 Apr 2020 19:28:48 -0400
Subject: [PATCH 17/34] openmp in conversions folder

---
 conversions/CMakeLists.txt | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/conversions/CMakeLists.txt b/conversions/CMakeLists.txt
index 0a98602f..19f1d6ba 100644
--- a/conversions/CMakeLists.txt
+++ b/conversions/CMakeLists.txt
@@ -1,3 +1,6 @@
+if(USE_OPENMP)
+    find_package(OpenMP)
+endif(USE_OPENMP)
 # If necessary, use the RELATIVE flag, otherwise each source file may be listed
 # with full pathname. RELATIVE may makes it easier to extract an executable name
 # automatically.
@@ -7,10 +10,16 @@ file( GLOB APP_SOURCES RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} *.c )
 foreach( testsourcefile ${APP_SOURCES} )
     # I used a simple string replace, to cut off .cpp.
     string( REPLACE ".c" "" testname ${testsourcefile} )
+
     add_executable( ${testname} ${testsourcefile} )
+
     # Make sure YourLib is linked to each app
     target_link_libraries( ${testname} function_timer )
     set_target_properties(${testname} PROPERTIES LINKER_LANGUAGE C)
+    if(OpenMP_C_FOUND)
+        target_link_libraries(${testname} OpenMP::OpenMP_C)
+    endif()
+
     install(TARGETS ${testname} DESTINATION "bin/conversions")
 
 endforeach( testsourcefile ${APP_SOURCES} )

From 8e7aa19113f74b689379f60cb758c7716fe6acfd Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Tue, 7 Apr 2020 19:29:39 -0400
Subject: [PATCH 18/34] cmake for 'computer_oriented_statistical_methods'

---
 CMakeLists.txt                                |  1 +
 .../CMakeLists.txt                            | 26 +++++++++++++++++++
 2 files changed, 27 insertions(+)
 create mode 100644 computer_oriented_statistical_methods/CMakeLists.txt

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 438e4439..994d4d05 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -17,6 +17,7 @@ add_subdirectory(conversions)
 add_subdirectory(misc)
 add_subdirectory(project_euler)
 add_subdirectory(sorting)
+add_subdirectory(computer_oriented_statistical_methods)
 
 if(USE_OPENMP)
     find_package(OpenMP)
diff --git a/computer_oriented_statistical_methods/CMakeLists.txt b/computer_oriented_statistical_methods/CMakeLists.txt
new file mode 100644
index 00000000..4e5d0fe2
--- /dev/null
+++ b/computer_oriented_statistical_methods/CMakeLists.txt
@@ -0,0 +1,26 @@
+if(USE_OPENMP)
+    find_package(OpenMP)
+endif(USE_OPENMP)
+# If necessary, use the RELATIVE flag, otherwise each source file may be listed
+# with full pathname. RELATIVE may makes it easier to extract an executable name
+# automatically.
+file( GLOB APP_SOURCES RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} *.c )
+# file( GLOB APP_SOURCES ${CMAKE_SOURCE_DIR}/*.c )
+# AUX_SOURCE_DIRECTORY(${CMAKE_CURRENT_SOURCE_DIR} APP_SOURCES)
+foreach( testsourcefile ${APP_SOURCES} )
+    # I used a simple string replace, to cut off .cpp.
+    string( REPLACE ".c" "" testname ${testsourcefile} )
+    string( REPLACE " " "_" testname ${testsourcefile} )
+
+    add_executable( ${testname} ${testsourcefile} )
+
+    # Make sure YourLib is linked to each app
+    target_link_libraries( ${testname} function_timer )
+    set_target_properties(${testname} PROPERTIES LINKER_LANGUAGE C)
+    if(OpenMP_C_FOUND)
+        target_link_libraries(${testname} OpenMP::OpenMP_C)
+    endif()
+
+    install(TARGETS ${testname} DESTINATION "bin/stats")
+
+endforeach( testsourcefile ${APP_SOURCES} )

From d7859b042cdebf20c8f61bff72c520e4216b7c14 Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Tue, 7 Apr 2020 19:31:29 -0400
Subject: [PATCH 19/34] removed dependency on "conio.h"

---
 .../Gauss_Elimination.c                       | 178 +++++++++---------
 computer_oriented_statistical_methods/MEAN.C  |  62 +++---
 .../MEDIAN.C                                  |  50 ++---
 .../Seidal.C                                  |  39 ++--
 .../lagrange_theorem.C                        |  71 +++----
 .../simpsons_1-3rd rule.c                     |  50 ++---
 6 files changed, 224 insertions(+), 226 deletions(-)

diff --git a/computer_oriented_statistical_methods/Gauss_Elimination.c b/computer_oriented_statistical_methods/Gauss_Elimination.c
index e35fa7ba..38f6fb31 100644
--- a/computer_oriented_statistical_methods/Gauss_Elimination.c
+++ b/computer_oriented_statistical_methods/Gauss_Elimination.c
@@ -1,100 +1,104 @@
-#include<stdio.h>
-#include<conio.h>
-void display(float a[20][20],int n)
-{
-	  int i,j;
-	  for(i=0;i<n;i++)
-	  {
-		    for(j=0;j<=n;j++)
-		    {
-			      printf("%.2f \t",a[i][j]);
-		    }
-		    printf("\n");
-	  }
-}
-float interchange(float m[20][20],int i,int n)
-{
-	  float tmp[20][20];
-	  float max=fabs(m[i][i]);
-	  int j,k=i;
+#include <stdio.h>
+#include <math.h>
 
-	  for(j=i;j<n;j++)
-	  {
-		    if(max<fabs(m[j][i]))
-		    {
-			      max=fabs(m[j][i]);
-			      k=j;
-		    }
-	  }
-	  for(j=0;j<=n;j++)
-	  {
-		    tmp[i][j]=m[i][j];
-		    m[i][j]=m[k][j];
-		    m[k][j]=tmp[i][j];
-	  }
-	  return m[20][20];
+#define ARRAY_SIZE 20
+
+void display(float a[ARRAY_SIZE][ARRAY_SIZE], int n)
+{
+	int i, j;
+	for (i = 0; i < n; i++)
+	{
+		for (j = 0; j <= n; j++)
+		{
+			printf("%.2f \t", a[i][j]);
+		}
+		printf("\n");
+	}
 }
-float eliminate(float m[20][20],int i,int n)
+
+float interchange(float m[ARRAY_SIZE][ARRAY_SIZE], int i, int n)
+{
+	float tmp[ARRAY_SIZE][ARRAY_SIZE];
+	float max = fabs(m[i][i]);
+	int j, k = i;
+
+	for (j = i; j < n; j++)
+	{
+		if (max < fabs(m[j][i]))
+		{
+			max = fabs(m[j][i]);
+			k = j;
+		}
+	}
+	for (j = 0; j <= n; j++)
+	{
+		tmp[i][j] = m[i][j];
+		m[i][j] = m[k][j];
+		m[k][j] = tmp[i][j];
+	}
+	return m[ARRAY_SIZE - 1][ARRAY_SIZE - 1];
+}
+float eliminate(float m[ARRAY_SIZE][ARRAY_SIZE], int i, int n)
 {
 	float tmp;
-	int k=1,l,j;
-	for(j=i;j<n-1;j++)
+	int k = 1, l, j;
+	for (j = i; j < n - 1; j++)
 	{
-		  tmp=-((m[i+k][i])/(m[i][i]));
-		  for(l=0;l<=n;l++)
-		  {
-			    m[i+k][l]=(m[i+k][l])+(m[i][l]*tmp);
-		  }
-		  k++;
+		tmp = -((m[i + k][i]) / (m[i][i]));
+		for (l = 0; l <= n; l++)
+		{
+			m[i + k][l] = (m[i + k][l]) + (m[i][l] * tmp);
+		}
+		k++;
 	}
-	return m[20][20];
+	return m[ARRAY_SIZE - 1][ARRAY_SIZE - 1];
 }
-void main()
+int main(void)
 {
-	  int i,j,n,k=0,l;
-	  float m[20][20],mul,tmp[20][20],val,ans[20];
-	  clrscr();
+	int i, j, n, k = 0, l;
+	float m[ARRAY_SIZE][ARRAY_SIZE], mul, tmp[ARRAY_SIZE][ARRAY_SIZE], val, ans[ARRAY_SIZE];
 
-	  printf("Total No.of Equations : ");
-	  scanf("%d",&n);
+	printf("Total No.of Equations : ");
+	scanf("%d", &n);
 
-	  printf("\n");
-	  for(i=0;i<n;i++)
-	  {
+	printf("\n");
+	for (i = 0; i < n; i++)
+	{
 
-		    printf("Enter Co-efficient Of Equations %d & Total --->>>\n",i+1);
-		    for(j=0;j<=n;j++)
-		    {
-			      printf("r%d%d : ",i,j);
-			      scanf("%f",&m[i][j]);
-		    }
-		    printf("\n");
-	  }
-	  printf(":::::::::::: Current Matrix ::::::::::::\n\n");
-	  display(m,n);
+		printf("Enter Co-efficient Of Equations %d & Total --->>>\n", i + 1);
+		for (j = 0; j <= n; j++)
+		{
+			printf("r%d%d : ", i, j);
+			scanf("%f", &m[i][j]);
+		}
+		printf("\n");
+	}
+	printf(":::::::::::: Current Matrix ::::::::::::\n\n");
+	display(m, n);
 
-	 for(i=0;i<n-1;i++)
-	 {
-		    printf("\n------->>>>>>>>>>>>>>>>>>>>>>>>-------- %d\n",i+1);
-		    m[20][20]=interchange(m,i,n);
-		    display(m,n);
-		    printf("\n_______________________________________\n");
-		    m[20][20]=eliminate(m,i,n);
-		    display(m,n);
-	  }
-	  printf("\n\n Values are : \n");
-	 for(i=n-1;i>=0;i--)
-	  {
-		    l=n-1;
-		    mul=0;
-		    for(j=0;j<k;j++)
-		    {
-			    mul=mul+m[i][l]*ans[l];
-			    l--;
-		    }
-		    k++;
-		    ans[i]=(m[i][n]-mul)/m[i][i];
-		    printf("X%d = %.2f\n",i+1,ans[i]);
-	  }
-getch();
+	for (i = 0; i < n - 1; i++)
+	{
+		printf("\n------->>>>>>>>>>>>>>>>>>>>>>>>-------- %d\n", i + 1);
+		m[ARRAY_SIZE - 1][ARRAY_SIZE - 1] = interchange(m, i, n);
+		display(m, n);
+		printf("\n_______________________________________\n");
+		m[ARRAY_SIZE - 1][ARRAY_SIZE - 1] = eliminate(m, i, n);
+		display(m, n);
+	}
+	printf("\n\n Values are : \n");
+	for (i = n - 1; i >= 0; i--)
+	{
+		l = n - 1;
+		mul = 0;
+		for (j = 0; j < k; j++)
+		{
+			mul = mul + m[i][l] * ans[l];
+			l--;
+		}
+		k++;
+		ans[i] = (m[i][n] - mul) / m[i][i];
+		printf("X%d = %.2f\n", i + 1, ans[i]);
+	}
+
+	return 0;
 }
diff --git a/computer_oriented_statistical_methods/MEAN.C b/computer_oriented_statistical_methods/MEAN.C
index e73b8b51..be36f57c 100644
--- a/computer_oriented_statistical_methods/MEAN.C
+++ b/computer_oriented_statistical_methods/MEAN.C
@@ -1,46 +1,38 @@
-#include<stdio.h>
-#include<conio.h>
-#include<math.h>
-void main()
+#include <stdio.h>
+#include <math.h>
+#include <limits.h>
+
+#define MAX_LEN INT_MAX
+
+int main(int argc, char **argv)
 {
-	int a[10],n,i,j,temp,sum=0;
+	int a[MAX_LEN], n = 10, i, j, temp, sum = 0;
 	float mean;
-	clrscr();
-	printf("Enter no. for Random Numbers :");
-	scanf("%d",&n);
-	for(i=0;i<n;i++)
+
+	if (argc == 2)
 	{
-		a[i]=rand()%100;
-	}
-	printf("Random Numbers Generated are :\n");
-	for(i=0;i<n;i++)
-	{
-		printf("\n%d",a[i]);
-	}
-	printf("\n");
-	printf("\nSorted Data:");
-	for(i=0;i<n;i++)
-	{
-		for(j=0;j<n;j++)
+		n = atoi(argv[1]);
+		if (n >= MAX_LEN)
 		{
-			if(a[i]<a[j])
-			{
-				temp=a[i];
-				a[i]=a[j];
-				a[j]=temp;
-			}
+			fprintf(stderr, "Maximum %d!\n", MAX_LEN);
+			return 1;
 		}
 	}
-	for(i=0;i<n;i++)
+
+	printf("Random Numbers Generated are : ");
+	for (i = 0; i < n; i++)
 	{
-		printf("\n%d",a[i]);
-		sum=sum+a[i];
+		a[i] = rand() % 100;
+		printf("%2d, ", a[i]);
 	}
-	mean=sum/(float)n;
+	putchar('\n');
+
+	for (i = 0; i < n; i++)
+		sum = sum + a[i];
+
+	mean = sum / (float)n;
 	printf("\nMean :");
-	printf("%f",mean);
+	printf("%f", mean);
 
-	getch();
+	return 0;
 }
-
-
diff --git a/computer_oriented_statistical_methods/MEDIAN.C b/computer_oriented_statistical_methods/MEDIAN.C
index fd2f70b0..ac5635b7 100644
--- a/computer_oriented_statistical_methods/MEDIAN.C
+++ b/computer_oriented_statistical_methods/MEDIAN.C
@@ -1,50 +1,50 @@
-#include<stdio.h>
-//#include<conio.h>
-#include<math.h>
+#include <stdio.h>
+#include <math.h>
 
-void main()
+int main()
 {
-	int a[10],n,i,j,temp;
-	float mean,median;
-	clrscr();
+	int a[10], n, i, j, temp;
+	float mean, median;
+
 	printf("Enter no. for Random Numbers :");
-	scanf("%d",&n);
-	for(i=0;i<n;i++)
+	scanf("%d", &n);
+	for (i = 0; i < n; i++)
 	{
-		a[i]=rand()%100;
+		a[i] = rand() % 100;
 	}
 	printf("Random Numbers Generated are :\n");
-	for(i=0;i<n;i++)
+	for (i = 0; i < n; i++)
 	{
-		printf("\n%d",a[i]);
+		printf("\n%d", a[i]);
 	}
 	printf("\n");
 	printf("\nSorted Data:");
-	for(i=0;i<n;i++)
+	for (i = 0; i < n; i++)
 	{
-		for(j=0;j<n;j++)
+		for (j = 0; j < n; j++)
 		{
-			if(a[i]<a[j])
+			if (a[i] < a[j])
 			{
-				temp=a[i];
-				a[i]=a[j];
-				a[j]=temp;
+				temp = a[i];
+				a[i] = a[j];
+				a[j] = temp;
 			}
 		}
 	}
-	for(i=0;i<n;i++)
+	for (i = 0; i < n; i++)
 	{
-		printf("\n%d",a[i]);
+		printf("\n%d", a[i]);
 	}
 
-	if(n%2==0)
+	if (n % 2 == 0)
 	{
-		median=(a[n/2]+a[(n/2)-1])/2;
+		median = (a[n / 2] + a[(n / 2) - 1]) / 2;
 	}
 	else
 	{
-		median=a[n/2];
+		median = a[n / 2];
 	}
-	printf("\nMedian is : %f",median);
-	getch();
+	printf("\nMedian is : %f", median);
+
+	return 0;
 }
diff --git a/computer_oriented_statistical_methods/Seidal.C b/computer_oriented_statistical_methods/Seidal.C
index 38e57e14..d073d879 100644
--- a/computer_oriented_statistical_methods/Seidal.C
+++ b/computer_oriented_statistical_methods/Seidal.C
@@ -1,26 +1,27 @@
-#include<stdio.h>
-#include<conio.h>
-#include<math.h>
-void main()
+#include <stdio.h>
+#include <math.h>
+
+int main()
 {
-	float a,b,c,a1,a2,a3,b1,b2,b3,c1,c2,c3,d1,d2,d3,x1,x2,x3;
-	clrscr();
+	float a, b, c, a1, a2, a3, b1, b2, b3, c1, c2, c3, d1, d2, d3, x1, x2, x3;
+
 	printf("Enter values of eq1:");
-	scanf("%f%f%f%f",&a1,&a2,&a3,&d1);
+	scanf("%f%f%f%f", &a1, &a2, &a3, &d1);
 	printf("Enter values of eq2:");
-	scanf("%f%f%f%f",&b1,&b2,&b3,&d2);
+	scanf("%f%f%f%f", &b1, &b2, &b3, &d2);
 	printf("Enter values of eq3:");
-	scanf("%f%f%f%f",&c1,&c2,&c3,&d3);
-	x1=x2=x3=0.0;
+	scanf("%f%f%f%f", &c1, &c2, &c3, &d3);
+	x1 = x2 = x3 = 0.0;
 	do
 	{
-		a=x1;
-		b=x2;
-		c=x3;
-		x1=(1/a1)*(d1-(a2*x2)-(a3*x3));
-		x2=(1/b2)*(d2-(b1*x1)-(b3*x3));
-		x3=(1/c3)*(d3-(c1*x1)-(c2*x2));
-	}while(fabs(x1-a)>0.0001&&fabs(x2-b)>0.0001&&fabs(x3-c)>0.0001);
-	printf("x1=%f\nx2=%f\nx3=%f",x1,x2,x3);
-	getch();
+		a = x1;
+		b = x2;
+		c = x3;
+		x1 = (1 / a1) * (d1 - (a2 * x2) - (a3 * x3));
+		x2 = (1 / b2) * (d2 - (b1 * x1) - (b3 * x3));
+		x3 = (1 / c3) * (d3 - (c1 * x1) - (c2 * x2));
+	} while (fabs(x1 - a) > 0.0001 && fabs(x2 - b) > 0.0001 && fabs(x3 - c) > 0.0001);
+	printf("x1=%f\nx2=%f\nx3=%f", x1, x2, x3);
+
+	return 0;
 }
\ No newline at end of file
diff --git a/computer_oriented_statistical_methods/lagrange_theorem.C b/computer_oriented_statistical_methods/lagrange_theorem.C
index 1b4694bb..397cd9f5 100644
--- a/computer_oriented_statistical_methods/lagrange_theorem.C
+++ b/computer_oriented_statistical_methods/lagrange_theorem.C
@@ -1,45 +1,46 @@
-#include<stdio.h>
-#include<conio.h>
-#include<stdlib.h>
-#include<math.h>
-void main()
-{
-	float x[20],y[20],a,sum,p;
-	int n,i,j;
-	clrscr();
-	printf("Enter the no of entry to insert->");
-	scanf("%d",&n);
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
 
-	for(i=0;i<n;i++)
+int main()
+{
+	float x[20], y[20], a, sum, p;
+	int n, i, j;
+
+	printf("Enter the no of entry to insert->");
+	scanf("%d", &n);
+
+	for (i = 0; i < n; i++)
 	{
-		printf("enter the value of x%d->",i);
-		scanf("%f",&x[i]);
-		printf("enter the value of y%d->",i);
-		scanf("%f",&y[i]);
+		printf("enter the value of x%d->", i);
+		scanf("%f", &x[i]);
+		printf("enter the value of y%d->", i);
+		scanf("%f", &y[i]);
 	}
 	printf("\n X \t\t Y \n");
-		printf("----------------------------\n");
-		for(i=0;i<n;i++)
+	printf("----------------------------\n");
+	for (i = 0; i < n; i++)
+	{
+		printf("%f\t", x[i]);
+		printf("%f\n", y[i]);
+	}
+	printf("\nenter the value of x for interpolation:");
+	scanf("%f", &a);
+	sum = 0;
+	for (i = 0; i < n; i++)
+	{
+		p = 1.0;
+		for (j = 0; j < n; j++)
 		{
-			printf("%f\t",x[i]);
-			printf("%f\n",y[i]);
-		}
-		printf("\nenter the value of x for interpolation:");
-		scanf("%f",&a)
-		sum=0;
-		for(i=0;i<n;i++)
-		{
-			p=1.0;
-			for(j=0;j<n;j++)
-			{
 
-			if(i !=j)
+			if (i != j)
 			{
-				p=p*(a-x[j])/(x[i]-x[j]);
+				p = p * (a - x[j]) / (x[i] - x[j]);
 			}
-			sum=sum+y[i]*p;
+			sum = sum + y[i] * p;
 		}
-		printf("ans is->%f",sum);
-		getch();
+		printf("ans is->%f", sum);
 
-}}
\ No newline at end of file
+		return 0;
+	}
+}
\ No newline at end of file
diff --git a/computer_oriented_statistical_methods/simpsons_1-3rd rule.c b/computer_oriented_statistical_methods/simpsons_1-3rd rule.c
index fe083b89..a055cc1e 100644
--- a/computer_oriented_statistical_methods/simpsons_1-3rd rule.c	
+++ b/computer_oriented_statistical_methods/simpsons_1-3rd rule.c	
@@ -1,41 +1,41 @@
-#include<stdio.h>
-#include<math.h> 
+#include <stdio.h>
+#include <math.h>
 
-float f(float x) 
+float f(float x)
 {
-	return 1.0+x*x*x; //This is the expresion of the function to integrate?
+	return 1.0 + x * x * x; //This is the expresion of the function to integrate?
 }
 
-void main()
+int main()
 {
-	int i,n;
-	float a,b,h,x,s2,s3,sum,integral;
-	
+	int i, n;
+	float a, b, h, x, s2, s3, sum, integral;
+
 	printf("enter the lower limit of the integration:");
-	scanf("%f",&a);
+	scanf("%f", &a);
 	printf("enter the upper limit of the integration:");
-	scanf("%f",&b);
+	scanf("%f", &b);
 	printf("enter the number of intervals:");
-	scanf("%d",&n);
-	
-	h=(b-a)/n;
-	sum=f(a)+f(b);
-	s2=s3=0.0;
+	scanf("%d", &n);
 
-  for(i=1;i<n;i+=3)
+	h = (b - a) / n;
+	sum = f(a) + f(b);
+	s2 = s3 = 0.0;
+
+	for (i = 1; i < n; i += 3)
 	{
-		x=a+i*h;
-		s3=s3+f(x)+f(x+h);
+		x = a + i * h;
+		s3 = s3 + f(x) + f(x + h);
 	}
 
-  for(i=3;i<n;i+=3)
+	for (i = 3; i < n; i += 3)
 	{
-		x=a+i*h;
-		s2=s2+f(x);
+		x = a + i * h;
+		s2 = s2 + f(x);
 	}
-	
-	integral=(h/3.0)*(sum+2*s2+4*s3);
-	printf("\nValue of the integral = %9.4f\n",integral);
-	
+
+	integral = (h / 3.0) * (sum + 2 * s2 + 4 * s3);
+	printf("\nValue of the integral = %9.4f\n", integral);
+
 	return 0;
 }
\ No newline at end of file

From 8d3d626e2596e874c763336d20df5bdc2c27ee9e Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Tue, 7 Apr 2020 21:25:45 -0400
Subject: [PATCH 20/34] + cmake searching folder

---
 CMakeLists.txt                          |  1 +
 searching/CMakeLists.txt                | 23 +++++++++++++++++++++++
 searching/pattern_search/CMakeLists.txt | 23 +++++++++++++++++++++++
 searching/pattern_search/Makefile       | 14 --------------
 4 files changed, 47 insertions(+), 14 deletions(-)
 create mode 100644 searching/CMakeLists.txt
 create mode 100644 searching/pattern_search/CMakeLists.txt
 delete mode 100644 searching/pattern_search/Makefile

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 994d4d05..e9163710 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -17,6 +17,7 @@ add_subdirectory(conversions)
 add_subdirectory(misc)
 add_subdirectory(project_euler)
 add_subdirectory(sorting)
+add_subdirectory(searching)
 add_subdirectory(computer_oriented_statistical_methods)
 
 if(USE_OPENMP)
diff --git a/searching/CMakeLists.txt b/searching/CMakeLists.txt
new file mode 100644
index 00000000..9ff68ec4
--- /dev/null
+++ b/searching/CMakeLists.txt
@@ -0,0 +1,23 @@
+if(USE_OPENMP)
+    find_package(OpenMP)
+endif()
+
+# If necessary, use the RELATIVE flag, otherwise each source file may be listed
+# with full pathname. RELATIVE may makes it easier to extract an executable name
+# automatically.
+file( GLOB APP_SOURCES RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} *.c )
+# file( GLOB APP_SOURCES ${CMAKE_SOURCE_DIR}/*.c )
+# AUX_SOURCE_DIRECTORY(${CMAKE_CURRENT_SOURCE_DIR} APP_SOURCES)
+foreach( testsourcefile ${APP_SOURCES} )
+    # I used a simple string replace, to cut off .cpp.
+    string( REPLACE ".c" "" testname ${testsourcefile} )
+    add_executable( ${testname} ${testsourcefile} )
+    # Make sure YourLib is linked to each app
+    target_link_libraries( ${testname} function_timer )
+    set_target_properties(${testname} PROPERTIES LINKER_LANGUAGE C)
+    if(OpenMP_C_FOUND)
+        target_link_libraries(${testname} OpenMP::OpenMP_C)
+    endif()
+    install(TARGETS ${testname} DESTINATION "bin/searching")
+
+endforeach( testsourcefile ${APP_SOURCES} )
diff --git a/searching/pattern_search/CMakeLists.txt b/searching/pattern_search/CMakeLists.txt
new file mode 100644
index 00000000..f23ecb5b
--- /dev/null
+++ b/searching/pattern_search/CMakeLists.txt
@@ -0,0 +1,23 @@
+if(USE_OPENMP)
+    find_package(OpenMP)
+endif()
+
+# If necessary, use the RELATIVE flag, otherwise each source file may be listed
+# with full pathname. RELATIVE may makes it easier to extract an executable name
+# automatically.
+file( GLOB APP_SOURCES RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} *.c )
+# file( GLOB APP_SOURCES ${CMAKE_SOURCE_DIR}/*.c )
+# AUX_SOURCE_DIRECTORY(${CMAKE_CURRENT_SOURCE_DIR} APP_SOURCES)
+foreach( testsourcefile ${APP_SOURCES} )
+    # I used a simple string replace, to cut off .cpp.
+    string( REPLACE ".c" "" testname ${testsourcefile} )
+    add_executable( ${testname} ${testsourcefile} )
+    # Make sure YourLib is linked to each app
+    target_link_libraries( ${testname} function_timer )
+    set_target_properties(${testname} PROPERTIES LINKER_LANGUAGE C)
+    if(OpenMP_C_FOUND)
+        target_link_libraries(${testname} OpenMP::OpenMP_C)
+    endif()
+    install(TARGETS ${testname} DESTINATION "bin/searching/pattern")
+
+endforeach( testsourcefile ${APP_SOURCES} )
diff --git a/searching/pattern_search/Makefile b/searching/pattern_search/Makefile
deleted file mode 100644
index b8c8aeb1..00000000
--- a/searching/pattern_search/Makefile
+++ /dev/null
@@ -1,14 +0,0 @@
-CC = gcc
-FLAG = -o
-
-all: naive_search  rabin_karp_search boyer_moore_search
-
-naive_search      : naive_search.c
-	$(CC) $(FLAG) naive_search naive_search.c
-rabin_karp_search : rabin_karp_search
-	$(CC) $(FLAG) rabin_karp_search rabin_karp_search.c
-boyer_moore_search: boyer_moore_search boyer_moore_search.c
-	$(CC) $(FLAG) boyer_moore_search boyer_moore_search.c
-
-clean:
-	rm naive_search rabin_karp_search boyer_moore_search

From d7b681fa001a404b6c51f461b0e4042ad5a4ef93 Mon Sep 17 00:00:00 2001
From: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
Date: Wed, 8 Apr 2020 01:26:11 +0000
Subject: [PATCH 21/34] updating DIRECTORY.md

---
 DIRECTORY.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/DIRECTORY.md b/DIRECTORY.md
index 6a44e327..1d9ae71d 100644
--- a/DIRECTORY.md
+++ b/DIRECTORY.md
@@ -11,7 +11,7 @@
   * [Mean](https://github.com/TheAlgorithms/C/blob/master/computer_oriented_statistical_methods/MEAN.C)
   * [Median](https://github.com/TheAlgorithms/C/blob/master/computer_oriented_statistical_methods/MEDIAN.C)
   * [Seidal](https://github.com/TheAlgorithms/C/blob/master/computer_oriented_statistical_methods/Seidal.C)
-  * [Simpson'S 1-3Rd Rule](https://github.com/TheAlgorithms/C/blob/master/computer_oriented_statistical_methods/simpson's%201-3rd%20rule.c)
+  * [Simpsons 1-3Rd Rule](https://github.com/TheAlgorithms/C/blob/master/computer_oriented_statistical_methods/simpsons_1-3rd%20rule.c)
   * [Variance](https://github.com/TheAlgorithms/C/blob/master/computer_oriented_statistical_methods/variance.c)
 
 ## Conversions

From 64789aed99c9a74a49a18a696ed2cf836fa56a76 Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Wed, 8 Apr 2020 09:30:46 -0400
Subject: [PATCH 22/34] bump cmake_c_standard to C11

---
 CMakeLists.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 528ad665..2988b71c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -13,7 +13,7 @@ include_directories(function_timer/include)
 # include_directories(${CMAKE_BINARY_DIR}/include)
 # link_directories(${CMAKE_BINARY_DIR}/lib/${CMAKE_BUILD_TYPE})
 
-set(CMAKE_C_STANDARD 99)
+set(CMAKE_C_STANDARD 11)
 set(CMAKE_C_STANDARD_REQUIRED ON)
 
 add_subdirectory(conversions)

From 1b826807ed981fc3317cdd72296a7e1d8f628827 Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Wed, 8 Apr 2020 09:41:12 -0400
Subject: [PATCH 23/34] code cleanup to prevent gcc warnings

---
 client_server/client.c                   | 129 ++++++++++++-----------
 conversions/decimal_to_octal_recursion.c |  15 +--
 misc/rselect.c                           | 101 +++++++++++-------
 misc/strong_Number.c                     |  36 +++----
 project_euler/Problem 03/sol1.c          |  42 +++++---
 project_euler/Problem 05/sol.c           |  18 ++--
 project_euler/Problem 14/sol1.c          |  47 ++++-----
 searching/Linear_Search.c                |  19 ++--
 searching/Other_Binary_Search.c          |  14 ++-
 sorting/Stooge_Sort.c                    |  16 +--
 sorting/multikey_quick_sort.c            |   3 +-
 11 files changed, 244 insertions(+), 196 deletions(-)

diff --git a/client_server/client.c b/client_server/client.c
index bd208362..a223478b 100644
--- a/client_server/client.c
+++ b/client_server/client.c
@@ -1,66 +1,71 @@
 
-// Write CPP code here 
-#include <netdb.h> 
-#include <stdio.h> 
-#include <stdlib.h> 
+// Write CPP code here
+#include <netdb.h>
+#include <stdio.h>
+#include <stdlib.h>
 #include <unistd.h>
-#include <string.h> 
-#include <sys/socket.h> 
-#define MAX 80 
-#define PORT 8080 
-#define SA struct sockaddr 
-void func(int sockfd) 
-{ 
-    char buff[MAX]; 
-    int n; 
-    for (;;) { 
-        bzero(buff, sizeof(buff)); 
-        printf("Enter the string : "); 
-        n = 0; 
-        while ((buff[n++] = getchar()) != '\n') 
-            ; 
-        write(sockfd, buff, sizeof(buff)); 
-        bzero(buff, sizeof(buff)); 
-        read(sockfd, buff, sizeof(buff)); 
-        printf("From Server : %s", buff); 
-        if ((strncmp(buff, "exit", 4)) == 0) { 
-            printf("Client Exit...\n"); 
-            break; 
-        } 
-    } 
-} 
-  
-int main() 
-{ 
-    int sockfd, connfd; 
-    struct sockaddr_in servaddr, cli; 
-  
-    // socket create and varification 
-    sockfd = socket(AF_INET, SOCK_STREAM, 0); 
-    if (sockfd == -1) { 
-        printf("socket creation failed...\n"); 
-        exit(0); 
-    } 
+#include <string.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#define MAX 80
+#define PORT 8080
+#define SA struct sockaddr
+void func(int sockfd)
+{
+    char buff[MAX];
+    int n;
+    for (;;)
+    {
+        bzero(buff, sizeof(buff));
+        printf("Enter the string : ");
+        n = 0;
+        while ((buff[n++] = getchar()) != '\n')
+            ;
+        write(sockfd, buff, sizeof(buff));
+        bzero(buff, sizeof(buff));
+        read(sockfd, buff, sizeof(buff));
+        printf("From Server : %s", buff);
+        if ((strncmp(buff, "exit", 4)) == 0)
+        {
+            printf("Client Exit...\n");
+            break;
+        }
+    }
+}
+
+int main()
+{
+    int sockfd, connfd;
+    struct sockaddr_in servaddr, cli;
+
+    // socket create and varification
+    sockfd = socket(AF_INET, SOCK_STREAM, 0);
+    if (sockfd == -1)
+    {
+        printf("socket creation failed...\n");
+        exit(0);
+    }
     else
-        printf("Socket successfully created..\n"); 
-    bzero(&servaddr, sizeof(servaddr)); 
-  
-    // assign IP, PORT 
-    servaddr.sin_family = AF_INET; 
-    servaddr.sin_addr.s_addr = inet_addr("127.0.0.1"); 
-    servaddr.sin_port = htons(PORT); 
-  
-    // connect the client socket to server socket 
-    if (connect(sockfd, (SA*)&servaddr, sizeof(servaddr)) != 0) { 
-        printf("connection with the server failed...\n"); 
-        exit(0); 
-    } 
+        printf("Socket successfully created..\n");
+    bzero(&servaddr, sizeof(servaddr));
+
+    // assign IP, PORT
+    servaddr.sin_family = AF_INET;
+    servaddr.sin_addr.s_addr = inet_addr("127.0.0.1");
+    servaddr.sin_port = htons(PORT);
+
+    // connect the client socket to server socket
+    if (connect(sockfd, (SA *)&servaddr, sizeof(servaddr)) != 0)
+    {
+        printf("connection with the server failed...\n");
+        exit(0);
+    }
     else
-        printf("connected to the server..\n"); 
-  
-    // function for chat 
-    func(sockfd); 
-  
-    // close the socket 
-    close(sockfd); 
-} 
+        printf("connected to the server..\n");
+
+    // function for chat
+    func(sockfd);
+
+    // close the socket
+    close(sockfd);
+}
diff --git a/conversions/decimal_to_octal_recursion.c b/conversions/decimal_to_octal_recursion.c
index 0d588951..a4d21b72 100644
--- a/conversions/decimal_to_octal_recursion.c
+++ b/conversions/decimal_to_octal_recursion.c
@@ -5,24 +5,25 @@
 #include <stdio.h>
 int decimal_to_octal(int decimal)
 {
-  if( (decimal<8) && (decimal>0) )
+  if ((decimal < 8) && (decimal > 0))
   {
     return decimal;
   }
-  else if(decimal==0)
+  else if (decimal == 0)
   {
     return 0;
   }
   else
   {
-    return ( (decimal_to_octal(decimal/8)*10) + decimal%8 );
+    return ((decimal_to_octal(decimal / 8) * 10) + decimal % 8);
   }
 }
-void main()
+int main()
 {
-  int octalNumber,decimalNumber;
+  int octalNumber, decimalNumber;
   printf("\nEnter your decimal number : ");
-  scanf("%d",&decimalNumber);
+  scanf("%d", &decimalNumber);
   octalNumber = decimal_to_octal(decimalNumber);
-  printf("\nThe octal of %d is : %d" ,decimalNumber,octalNumber);
+  printf("\nThe octal of %d is : %d", decimalNumber, octalNumber);
+  return 0;
 }
diff --git a/misc/rselect.c b/misc/rselect.c
index 9679bf00..af9be942 100644
--- a/misc/rselect.c
+++ b/misc/rselect.c
@@ -1,54 +1,77 @@
 #include <stdio.h>
-#include<stdlib.h>
-#include<time.h>
-void swap(int *a ,int *b)
-{int t;t =*a;*a=*b;*b=t;}
-int part(int a[],int l,int r,int n,int pivot,int pindex)
-{int p1=l,p2=r;
-    while(p2>p1)
+#include <stdlib.h>
+#include <time.h>
+void swap(int *a, int *b)
+{
+    int t;
+    t = *a;
+    *a = *b;
+    *b = t;
+}
+int part(int a[], int l, int r, int n, int pivot, int pindex)
+{
+    int p1 = l, p2 = r;
+    while (p2 > p1)
     {
-        if (a[p1] > pivot && a[p2]<pivot)
-        {swap(&a[p1],&a[p2]);}
+        if (a[p1] > pivot && a[p2] < pivot)
+        {
+            swap(&a[p1], &a[p2]);
+        }
         else
         {
-            if (a[p1] <=pivot)
-            {p1++;}
-            if (a[p2]>=pivot)
-            {p2--;}
+            if (a[p1] <= pivot)
+            {
+                p1++;
+            }
+            if (a[p2] >= pivot)
+            {
+                p2--;
+            }
         }
     }
-    swap(&a[pindex],&a[p2]);
+    swap(&a[pindex], &a[p2]);
     return p2;
 }
-int rselect(int a[],int l,int r,int n,int o)
+int rselect(int a[], int l, int r, int n, int o)
 {
-    int pivot,pindex,pactual;
-    if (r>l)
+    int pivot, pindex, pactual;
+    if (r > l)
     {
-    pindex = rand()%(r-l+1);
-    pivot = a[pindex];
-    pactual = part(a,l,r,n,pivot,pindex);
-    
-    if (pactual == o)
-    {return a[pactual];}
-    
-    if (o < pactual)
-    {rselect(a,l,pactual-1,n,o);}
-    
-    if (o>pactual)
-    {rselect(a,pactual+1,r,n,o-pactual);}
+        pindex = rand() % (r - l + 1);
+        pivot = a[pindex];
+        pactual = part(a, l, r, n, pivot, pindex);
+
+        if (pactual == o)
+        {
+            return a[pactual];
+        }
+
+        if (o < pactual)
+        {
+            rselect(a, l, pactual - 1, n, o);
+        }
+
+        if (o > pactual)
+        {
+            rselect(a, pactual + 1, r, n, o - pactual);
+        }
     }
-    if (r==l)
-    {return a[l];}
+    if (r == l)
+    {
+        return a[l];
+    }
+    return -1;
 }
 int main()
-{srand(time(NULL));
-    int n,o,i,*a;
-   scanf("%d %d",&n,&o);
-   a = (int*)malloc(n*sizeof(int));
-   for (i=0;i<n;i++)
-   {scanf("%d",a+i);}
-printf("\n\n%d",rselect(a,0,n-1,n,o));
+{
+    srand(time(NULL));
+    int n, o, i, *a;
+    scanf("%d %d", &n, &o);
+    a = (int *)malloc(n * sizeof(int));
+    for (i = 0; i < n; i++)
+    {
+        scanf("%d", a + i);
+    }
+    printf("\n\n%d", rselect(a, 0, n - 1, n, o));
     return 0;
 }
-
diff --git a/misc/strong_Number.c b/misc/strong_Number.c
index 9b5d3527..baff3623 100644
--- a/misc/strong_Number.c
+++ b/misc/strong_Number.c
@@ -1,38 +1,38 @@
 /**
  * Modified on 07/12/2017, Kyler Smith
  *
- * A number is called strong number if sum of the 
+ * A number is called strong number if sum of the
  * 	factorial of its digit is equal to number itself.
  */
 
-#include<stdio.h>
-
+#include <stdio.h>
 
 void strng(int a)
 {
-	int j=a;
-	int sum=0;
-	int b,i,fact=1;	
-	while(a>0)
+	int j = a;
+	int sum = 0;
+	int b, i, fact = 1;
+	while (a > 0)
 	{
-		fact=1;
-		b=a%10;
-		for(i=1;i<=b;i++)
+		fact = 1;
+		b = a % 10;
+		for (i = 1; i <= b; i++)
 		{
-			fact=fact*i;
+			fact = fact * i;
 		}
-		a=a/10;
-		sum=sum+fact;
+		a = a / 10;
+		sum = sum + fact;
 	}
-	if(sum==j)
-	printf("%d is a strong number",j);
+	if (sum == j)
+		printf("%d is a strong number", j);
 	else
-	printf("%d is not a strong number",j);
+		printf("%d is not a strong number", j);
 }
-void main()
+int main()
 {
 	int a;
 	printf("Enter the number to check");
-	scanf("%d",&a);
+	scanf("%d", &a);
 	strng(a);
+	return 0;
 }
diff --git a/project_euler/Problem 03/sol1.c b/project_euler/Problem 03/sol1.c
index 369ec72d..680b2882 100644
--- a/project_euler/Problem 03/sol1.c	
+++ b/project_euler/Problem 03/sol1.c	
@@ -6,47 +6,61 @@ e.g. for 10, largest prime factor = 5. For 17, largest prime factor = 17.
 #include <stdio.h>
 #include <math.h>
 
-int isprime(int no) {
+int isprime(int no)
+{
 	int sq;
 
-	if (no == 2) {
+	if (no == 2)
+	{
 		return 1;
 	}
-	else if (no%2 == 0) {
+	else if (no % 2 == 0)
+	{
 		return 0;
 	}
 	sq = ((int)(sqrt(no))) + 1;
-	for (int i = 3; i < sq; i + 2) {
-		if (no%i == 0) {
+	for (int i = 3; i < sq; i += 2)
+	{
+		if (no % i == 0)
+		{
 			return 0;
 		}
 	}
 	return 1;
 }
 
-int main() {
+int main()
+{
 	int maxNumber = 0;
 	int n = 0;
 	int n1;
 	scanf("%d", &n);
 	if (isprime(n) == 1)
 		printf("%d", n);
-	else {
-		while (n % 2 == 0) {
+	else
+	{
+		while (n % 2 == 0)
+		{
 			n = n / 2;
 		}
-		if (isprime(n) == 1) {
+		if (isprime(n) == 1)
+		{
 			printf("%d\n", n);
 		}
-		else {
+		else
+		{
 			n1 = ((int)(sqrt(n))) + 1;
-			for (int i = 3; i < n1; i + 2) {
-				if (n%i == 0) {
-					if (isprime((int)(n / i)) == 1) {
+			for (int i = 3; i < n1; i += 2)
+			{
+				if (n % i == 0)
+				{
+					if (isprime((int)(n / i)) == 1)
+					{
 						maxNumber = n / i;
 						break;
 					}
-					else if (isprime(i) == 1) {
+					else if (isprime(i) == 1)
+					{
 						maxNumber = i;
 					}
 				}
diff --git a/project_euler/Problem 05/sol.c b/project_euler/Problem 05/sol.c
index 12599033..b3190d2e 100644
--- a/project_euler/Problem 05/sol.c	
+++ b/project_euler/Problem 05/sol.c	
@@ -1,28 +1,34 @@
 #include <stdio.h>
 
-unsigned long gcd(unsigned long a, unsigned long b) {
+unsigned long gcd(unsigned long a, unsigned long b)
+{
     unsigned long r;
-    if (a > b) {
+    if (a > b)
+    {
         unsigned long t = a;
         a = b;
         b = t;
     }
-    while (r = a % b) {
+    while ((r = (a % b)))
+    {
         a = b;
         b = r;
     }
     return b;
 }
 
-unsigned long lcm(unsigned long a, unsigned long b) {
+unsigned long lcm(unsigned long a, unsigned long b)
+{
     unsigned long long p = (unsigned long long)a * b;
     return p / gcd(a, b);
 }
 
-int main(void) {
+int main(void)
+{
     unsigned long ans = 1;
     unsigned long i;
-    for (i = 1; i <= 20; i++) {
+    for (i = 1; i <= 20; i++)
+    {
         ans = lcm(ans, i);
     }
     printf("%lu\n", ans);
diff --git a/project_euler/Problem 14/sol1.c b/project_euler/Problem 14/sol1.c
index e8af5ad6..aabbd60d 100644
--- a/project_euler/Problem 14/sol1.c	
+++ b/project_euler/Problem 14/sol1.c	
@@ -2,27 +2,24 @@
 #include <stdlib.h>
 
 #ifdef _OPENMP
-    #include <omp.h>
-    #pragma message ("Using OpenMP parallelization")
-#else
-    #pragma message ("Not using OpenMP parallelization")
+#include <omp.h>
 #endif
 
 /**
- * Computes the length of collatz sequence for a given 
- * starting number 
+ * Computes the length of collatz sequence for a given
+ * starting number
  **/
 long long collatz(long long start_num)
 {
     long long length = 1;
-    
-    while (start_num != 1)      /* loop till we reach 1 */
+
+    while (start_num != 1) /* loop till we reach 1 */
     {
-        if(start_num & 0x01)    /* check for odd */
+        if (start_num & 0x01) /* check for odd */
             start_num = 3 * start_num + 1;
         else
-            start_num >>= 1;    /* simpler divide by 2 */
-        length ++;
+            start_num >>= 1; /* simpler divide by 2 */
+        length++;
     }
 
     return length;
@@ -33,39 +30,39 @@ int main(int argc, char **argv)
     long long max_len = 0, max_len_num = 0;
     long long MAX_NUM = 1000000;
 
-    if (argc == 2)  /* set commandline argumnet as the maximum iteration number */
+    if (argc == 2) /* set commandline argumnet as the maximum iteration number */
     {
         MAX_NUM = atoll(argv[1]);
         printf("Maximum number: %lld\n", MAX_NUM);
     }
 
-    /** 
-     * Since the computational values for each iteration step are independent, 
-     * we can compute them in parallel. However, the maximum values should be 
+/**
+     * Since the computational values for each iteration step are independent,
+     * we can compute them in parallel. However, the maximum values should be
      * updated in synchrony so that we do not get into a "race condition".
-     * 
+     *
      * To compile with supporintg gcc or clang, the flag "-fopenmp" should be passes
      * while with Microsoft C compiler, the flag "/fopenmp" should be used.
-     * 
+     *
      * Automatically detects for OPENMP using the _OPENMP macro.
      **/
-    #ifdef _OPENMP
-    #pragma omp parallel for shared(max_len, max_len_num) schedule(guided)
-    #endif
+#ifdef _OPENMP
+#pragma omp parallel for shared(max_len, max_len_num) schedule(guided)
+#endif
     for (long long i = 1; i < MAX_NUM; i++)
     {
         long long L = collatz(i);
         if (L > max_len)
         {
-            max_len = L;        /* length of sequence */
-            max_len_num = i;    /* starting number */
+            max_len = L;     /* length of sequence */
+            max_len_num = i; /* starting number */
         }
 
-        #if defined(_OPENMP) && defined(DEBUG)
+#if defined(_OPENMP) && defined(DEBUG)
         printf("Thread: %2d\t %3lld: \t%5lld\n", omp_get_thread_num(), i, L);
-        #elif defined(DEBUG)
+#elif defined(DEBUG)
         printf("%3lld: \t%5lld\n", i, L);
-        #endif
+#endif
     }
 
     printf("Start: %3lld: \tLength: %5lld\n", max_len_num, max_len);
diff --git a/searching/Linear_Search.c b/searching/Linear_Search.c
index e507bb0c..5c85d697 100644
--- a/searching/Linear_Search.c
+++ b/searching/Linear_Search.c
@@ -1,27 +1,32 @@
 #include <stdio.h>
 
-int linearsearch(int *arr, int size, int val){
+int linearsearch(int *arr, int size, int val)
+{
 	int i;
-	for (i = 0; i < size; i++){
+	for (i = 0; i < size; i++)
+	{
 		if (arr[i] == val)
 			return 1;
 	}
 	return 0;
 }
 
-void main(){
-	int n,i,v;
+int main()
+{
+	int n, i, v;
 	printf("Enter the size of the array:\n");
-	scanf("%d",&n); //Taking input for the size of Array
+	scanf("%d", &n); //Taking input for the size of Array
 
 	int a[n];
 	printf("Enter the contents for an array of size %d:\n", n);
-	for (i = 0; i < n; i++)	scanf("%d", &a[i]);// accepts the values of array elements until the loop terminates//
+	for (i = 0; i < n; i++)
+		scanf("%d", &a[i]); // accepts the values of array elements until the loop terminates//
 
 	printf("Enter the value to be searched:\n");
 	scanf("%d", &v); //Taking input the value to be searched
-	if (linearsearch(a,n,v))
+	if (linearsearch(a, n, v))
 		printf("Value %d is in the array.\n", v);
 	else
 		printf("Value %d is not in the array.\n", v);
+	return 0;
 }
diff --git a/searching/Other_Binary_Search.c b/searching/Other_Binary_Search.c
index 3337ce19..85a65099 100644
--- a/searching/Other_Binary_Search.c
+++ b/searching/Other_Binary_Search.c
@@ -2,7 +2,6 @@
 #include <stdlib.h>
 #define len 5
 
-
 int binarySearch(int array[], int leng, int searchX)
 {
 	int pos = -1, right, left, i = 0;
@@ -10,14 +9,14 @@ int binarySearch(int array[], int leng, int searchX)
 	left = 0;
 	right = leng - 1;
 
-	while(left <= right)
+	while (left <= right)
 	{
 		pos = left + (right - left) / 2;
-		if(array[pos] == searchX)
+		if (array[pos] == searchX)
 		{
 			return pos;
 		}
-		else if(array[pos] > searchX)
+		else if (array[pos] > searchX)
 		{
 			right = pos - 1;
 		}
@@ -29,10 +28,9 @@ int binarySearch(int array[], int leng, int searchX)
 	return -1; /* not found */
 }
 
-
-void main(int argc, char *argv[])
+int main(int argc, char *argv[])
 {
-	int array[len] = { 5, 8 , 10 , 14 ,16 };
+	int array[len] = {5, 8, 10, 14, 16};
 
 	int position;
 	position = binarySearch(array, len, 5);
@@ -44,5 +42,5 @@ void main(int argc, char *argv[])
 		printf("The number %d exist in array at position : %d \n", 5, position);
 	}
 
-
+	return 0;
 }
diff --git a/sorting/Stooge_Sort.c b/sorting/Stooge_Sort.c
index 8b265adb..f7ef862f 100644
--- a/sorting/Stooge_Sort.c
+++ b/sorting/Stooge_Sort.c
@@ -1,24 +1,24 @@
 #include <stdio.h>
-void stoogesort(int [], int, int);
- 
-void main()
+void stoogesort(int[], int, int);
+
+int main()
 {
     int arr[100], i, n;
- 
+
     printf("How many elements do you want to sort: ");
     scanf("%d", &n);
-    for (i = 0;i < n; i++)
+    for (i = 0; i < n; i++)
         scanf(" %d", &arr[i]);
     stoogesort(arr, 0, n - 1);
     printf("Sorted array : \n");
-    for (i = 0;i < n;i++)
+    for (i = 0; i < n; i++)
     {
         printf("%d ", arr[i]);
     }
     printf("\n");
+    return 0;
 }
- 
- 
+
 void stoogesort(int arr[], int i, int j)
 {
     int temp, k;
diff --git a/sorting/multikey_quick_sort.c b/sorting/multikey_quick_sort.c
index 7077aa53..685c1979 100644
--- a/sorting/multikey_quick_sort.c
+++ b/sorting/multikey_quick_sort.c
@@ -259,7 +259,7 @@ void insert2(char *s)
 
     Tptr pp, *p;
     p = &root;
-    while (pp = *p)
+    while (pp == *p)
     {
         if ((d = *s - pp->splitchar) == 0)
         {
@@ -390,7 +390,6 @@ void nearsearch(Tptr p, char *s, int d)
         nearsearch(p->hikid, s, d);
 }
 
-
 #define NUMBER_OF_STRING 3
 
 int main(int argc, char *argv[])

From 1d8d07efc9c0f3bdecc4faef991f0a1ac77b2146 Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Wed, 8 Apr 2020 09:45:12 -0400
Subject: [PATCH 24/34] gets not a C11 standard, superceded by fgets

---
 conversions/hexadecimal_to_octal.c | 175 +++++++++++++++--------------
 1 file changed, 88 insertions(+), 87 deletions(-)

diff --git a/conversions/hexadecimal_to_octal.c b/conversions/hexadecimal_to_octal.c
index 097ba87c..7340dcd1 100644
--- a/conversions/hexadecimal_to_octal.c
+++ b/conversions/hexadecimal_to_octal.c
@@ -4,81 +4,82 @@
 
 int main()
 {
-    char hex[17];
+#define MAX_STR_LEN 17
+    char hex[MAX_STR_LEN];
     long long octal, bin, place;
     int i = 0, rem, val;
 
     /* Input hexadecimal number from user */
     printf("Enter any hexadecimal number: ");
-    gets(hex);
+    fgets(hex, MAX_STR_LEN, stdin);
 
     octal = 0ll;
     bin = 0ll;
     place = 0ll;
 
     /* Hexadecimal to binary conversion */
-    for(i=0; hex[i]!='\0'; i++)
+    for (i = 0; hex[i] != '\0'; i++)
     {
         bin = bin * place;
 
-        switch(hex[i])
+        switch (hex[i])
         {
-            case '0':
-                bin += 0;
-                break;
-            case '1':
-                bin += 1;
-                break;
-            case '2':
-                bin += 10;
-                break;
-            case '3':
-                bin += 11;
-                break;
-            case '4':
-                bin += 100;
-                break;
-            case '5':
-                bin += 101;
-                break;
-            case '6':
-                bin += 110;
-                break;
-            case '7':
-                bin += 111;
-                break;
-            case '8':
-                bin += 1000;
-                break;
-            case '9':
-                bin += 1001;
-                break;
-            case 'a':
-            case 'A':
-                bin += 1010;
-                break;
-            case 'b':
-            case 'B':
-                bin += 1011;
-                break;
-            case 'c':
-            case 'C':
-                bin += 1100;
-                break;
-            case 'd':
-            case 'D':
-                bin += 1101;
-                break;
-            case 'e':
-            case 'E':
-                bin += 1110;
-                break;
-            case 'f':
-            case 'F':
-                bin += 1111;
-                break;
-            default:
-                printf("Invalid hexadecimal input.");
+        case '0':
+            bin += 0;
+            break;
+        case '1':
+            bin += 1;
+            break;
+        case '2':
+            bin += 10;
+            break;
+        case '3':
+            bin += 11;
+            break;
+        case '4':
+            bin += 100;
+            break;
+        case '5':
+            bin += 101;
+            break;
+        case '6':
+            bin += 110;
+            break;
+        case '7':
+            bin += 111;
+            break;
+        case '8':
+            bin += 1000;
+            break;
+        case '9':
+            bin += 1001;
+            break;
+        case 'a':
+        case 'A':
+            bin += 1010;
+            break;
+        case 'b':
+        case 'B':
+            bin += 1011;
+            break;
+        case 'c':
+        case 'C':
+            bin += 1100;
+            break;
+        case 'd':
+        case 'D':
+            bin += 1101;
+            break;
+        case 'e':
+        case 'E':
+            bin += 1110;
+            break;
+        case 'f':
+        case 'F':
+            bin += 1111;
+            break;
+        default:
+            printf("Invalid hexadecimal input.");
         }
 
         place = 10000;
@@ -87,36 +88,36 @@ int main()
     place = 1;
 
     /* Binary to octal conversion */
-    while(bin > 0)
+    while (bin > 0)
     {
         rem = bin % 1000;
 
-        switch(rem)
+        switch (rem)
         {
-            case 0:
-                val = 0;
-                break;
-            case 1:
-                val = 1;
-                break;
-            case 10:
-                val = 2;
-                break;
-            case 11:
-                val = 3;
-                break;
-            case 100:
-                val = 4;
-                break;
-            case 101:
-                val = 5;
-                break;
-            case 110:
-                val = 6;
-                break;
-            case 111:
-                val = 7;
-                break;
+        case 0:
+            val = 0;
+            break;
+        case 1:
+            val = 1;
+            break;
+        case 10:
+            val = 2;
+            break;
+        case 11:
+            val = 3;
+            break;
+        case 100:
+            val = 4;
+            break;
+        case 101:
+            val = 5;
+            break;
+        case 110:
+            val = 6;
+            break;
+        case 111:
+            val = 7;
+            break;
         }
 
         octal = (val * place) + octal;
@@ -129,4 +130,4 @@ int main()
     printf("Octal number = %lld", octal);
 
     return 0;
-} 
+}

From de027fe4ff28aa30ffc61e8df0be368c4dfe0b8f Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Wed, 8 Apr 2020 09:46:44 -0400
Subject: [PATCH 25/34] using long long int for pritf compatibility

---
 project_euler/Problem 08/sol1.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/project_euler/Problem 08/sol1.c b/project_euler/Problem 08/sol1.c
index 1c57045e..4404549c 100644
--- a/project_euler/Problem 08/sol1.c	
+++ b/project_euler/Problem 08/sol1.c	
@@ -1,13 +1,12 @@
 #include <stdio.h>
-#include <stdint.h>
 #include <stdlib.h>
 
-int64_t get_product(FILE *fp, long start_pos, int num_digits)
+long long int get_product(FILE *fp, long start_pos, int num_digits)
 {
-    char ch = ' ';    /* temporary variable to store character read from file */
-    uint8_t num = 0;  /* temporary variable to store digit read */
-    int64_t prod = 1; /* product accumulator */
-    int count = 0;    /* we use this variable to count number of bytes of file read */
+    char ch = ' ';          /* temporary variable to store character read from file */
+    uint8_t num = 0;        /* temporary variable to store digit read */
+    long long int prod = 1; /* product accumulator */
+    int count = 0;          /* we use this variable to count number of bytes of file read */
 
     /* accumulate product for num_digits */
     for (int i = 0; i < num_digits; i++, count++)
@@ -49,7 +48,7 @@ int main(int argc, char *argv[])
 {
     int position = 0;
     int num_digits = 4;
-    int64_t prod, max_prod = 0;
+    long long int prod, max_prod = 0;
 
     /* if second command-line argument is ge=iven,
      * use it as the number of digits to compute

From 63206ab47a371b8bcdff1f3da49de515188cad14 Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Wed, 8 Apr 2020 09:48:04 -0400
Subject: [PATCH 26/34] use long long int for printf compatibility

---
 project_euler/Problem 08/sol2.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/project_euler/Problem 08/sol2.c b/project_euler/Problem 08/sol2.c
index 67371886..9877b92d 100644
--- a/project_euler/Problem 08/sol2.c	
+++ b/project_euler/Problem 08/sol2.c	
@@ -10,7 +10,7 @@ int main(int argc, char *argv[])
     char ch;
     uint8_t num, num_prev;
     uint8_t *buffer = NULL;
-    int64_t prod = 1, max_prod = 0;
+    long long int prod = 1, max_prod = 0;
 
     /* if second command-line argument is given,
      * use it as the number of digits to compute

From d5143ff07c6e6760f05a7d4baa2bf0be42ba07f6 Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Wed, 8 Apr 2020 09:52:08 -0400
Subject: [PATCH 27/34] stdlib include for rand function

---
 computer_oriented_statistical_methods/MEDIAN.C | 1 +
 1 file changed, 1 insertion(+)

diff --git a/computer_oriented_statistical_methods/MEDIAN.C b/computer_oriented_statistical_methods/MEDIAN.C
index ac5635b7..ad24cdef 100644
--- a/computer_oriented_statistical_methods/MEDIAN.C
+++ b/computer_oriented_statistical_methods/MEDIAN.C
@@ -1,5 +1,6 @@
 #include <stdio.h>
 #include <math.h>
+#include <stdlib.h>
 
 int main()
 {

From 66ef12de2c3fd951444c005a4f912d1691020681 Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Wed, 8 Apr 2020 09:59:44 -0400
Subject: [PATCH 28/34] remove stdint.h dependency

---
 project_euler/Problem 08/sol1.c | 2 +-
 project_euler/Problem 08/sol2.c | 5 ++---
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/project_euler/Problem 08/sol1.c b/project_euler/Problem 08/sol1.c
index 4404549c..2615648b 100644
--- a/project_euler/Problem 08/sol1.c	
+++ b/project_euler/Problem 08/sol1.c	
@@ -4,7 +4,7 @@
 long long int get_product(FILE *fp, long start_pos, int num_digits)
 {
     char ch = ' ';          /* temporary variable to store character read from file */
-    uint8_t num = 0;        /* temporary variable to store digit read */
+    unsigned char num = 0;  /* temporary variable to store digit read */
     long long int prod = 1; /* product accumulator */
     int count = 0;          /* we use this variable to count number of bytes of file read */
 
diff --git a/project_euler/Problem 08/sol2.c b/project_euler/Problem 08/sol2.c
index 9877b92d..0cb79da5 100644
--- a/project_euler/Problem 08/sol2.c	
+++ b/project_euler/Problem 08/sol2.c	
@@ -1,6 +1,5 @@
 #include <stdio.h>
 #include <stdlib.h>
-#include <stdint.h>
 #include <string.h> /* for memmove */
 
 int main(int argc, char *argv[])
@@ -8,8 +7,8 @@ int main(int argc, char *argv[])
     int position = 0, num_bad_chars = 0;
     int num_digits = 4;
     char ch;
-    uint8_t num, num_prev;
-    uint8_t *buffer = NULL;
+    unsigned char num, num_prev;
+    unsigned char *buffer = NULL;
     long long int prod = 1, max_prod = 0;
 
     /* if second command-line argument is given,

From 44a89fb3bab68eb46ba431bf96ee3149c0d51b01 Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Wed, 8 Apr 2020 10:02:08 -0400
Subject: [PATCH 29/34] fixed stdint.h artefact

---
 project_euler/Problem 08/sol2.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/project_euler/Problem 08/sol2.c b/project_euler/Problem 08/sol2.c
index 0cb79da5..5a9e2155 100644
--- a/project_euler/Problem 08/sol2.c	
+++ b/project_euler/Problem 08/sol2.c	
@@ -19,7 +19,7 @@ int main(int argc, char *argv[])
         num_digits = atoi(argv[1]);
 
     /* allocate memory to store past values */
-    buffer = calloc(num_digits, sizeof(uint8_t));
+    buffer = calloc(num_digits, sizeof(unsigned char));
     if (!buffer)
     {
         perror("Unable to allocate memory for buffer");

From d2e1b7fc98b6c916ccf57f07d21b4fda5624f61b Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Wed, 8 Apr 2020 10:08:25 -0400
Subject: [PATCH 30/34] added stdlib.h dependency for rand()

---
 computer_oriented_statistical_methods/MEAN.C | 1 +
 1 file changed, 1 insertion(+)

diff --git a/computer_oriented_statistical_methods/MEAN.C b/computer_oriented_statistical_methods/MEAN.C
index be36f57c..160c8b75 100644
--- a/computer_oriented_statistical_methods/MEAN.C
+++ b/computer_oriented_statistical_methods/MEAN.C
@@ -1,5 +1,6 @@
 #include <stdio.h>
 #include <math.h>
+#include <stdlib.h>
 #include <limits.h>
 
 #define MAX_LEN INT_MAX

From 952d521a3c27fc4128d51d06e4508792b0ec630b Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Wed, 8 Apr 2020 10:28:58 -0400
Subject: [PATCH 31/34] better name - numerical methods

---
 CMakeLists.txt                                                  | 2 +-
 .../CMakeLists.txt                                              | 0
 .../Gauss_Elimination.c                                         | 0
 .../MEAN.C                                                      | 0
 .../MEDIAN.C                                                    | 0
 .../Seidal.C                                                    | 0
 .../lagrange_theorem.C                                          | 0
 .../simpsons_1-3rd rule.c                                       | 0
 .../variance.c                                                  | 0
 9 files changed, 1 insertion(+), 1 deletion(-)
 rename {computer_oriented_statistical_methods => numerical_methods}/CMakeLists.txt (100%)
 rename {computer_oriented_statistical_methods => numerical_methods}/Gauss_Elimination.c (100%)
 rename {computer_oriented_statistical_methods => numerical_methods}/MEAN.C (100%)
 rename {computer_oriented_statistical_methods => numerical_methods}/MEDIAN.C (100%)
 rename {computer_oriented_statistical_methods => numerical_methods}/Seidal.C (100%)
 rename {computer_oriented_statistical_methods => numerical_methods}/lagrange_theorem.C (100%)
 rename {computer_oriented_statistical_methods => numerical_methods}/simpsons_1-3rd rule.c (100%)
 rename {computer_oriented_statistical_methods => numerical_methods}/variance.c (100%)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 2988b71c..455926f8 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -21,7 +21,7 @@ add_subdirectory(misc)
 add_subdirectory(project_euler)
 add_subdirectory(sorting)
 add_subdirectory(searching)
-add_subdirectory(computer_oriented_statistical_methods)
+add_subdirectory(numerical_methods)
 
 if(USE_OPENMP)
     find_package(OpenMP)
diff --git a/computer_oriented_statistical_methods/CMakeLists.txt b/numerical_methods/CMakeLists.txt
similarity index 100%
rename from computer_oriented_statistical_methods/CMakeLists.txt
rename to numerical_methods/CMakeLists.txt
diff --git a/computer_oriented_statistical_methods/Gauss_Elimination.c b/numerical_methods/Gauss_Elimination.c
similarity index 100%
rename from computer_oriented_statistical_methods/Gauss_Elimination.c
rename to numerical_methods/Gauss_Elimination.c
diff --git a/computer_oriented_statistical_methods/MEAN.C b/numerical_methods/MEAN.C
similarity index 100%
rename from computer_oriented_statistical_methods/MEAN.C
rename to numerical_methods/MEAN.C
diff --git a/computer_oriented_statistical_methods/MEDIAN.C b/numerical_methods/MEDIAN.C
similarity index 100%
rename from computer_oriented_statistical_methods/MEDIAN.C
rename to numerical_methods/MEDIAN.C
diff --git a/computer_oriented_statistical_methods/Seidal.C b/numerical_methods/Seidal.C
similarity index 100%
rename from computer_oriented_statistical_methods/Seidal.C
rename to numerical_methods/Seidal.C
diff --git a/computer_oriented_statistical_methods/lagrange_theorem.C b/numerical_methods/lagrange_theorem.C
similarity index 100%
rename from computer_oriented_statistical_methods/lagrange_theorem.C
rename to numerical_methods/lagrange_theorem.C
diff --git a/computer_oriented_statistical_methods/simpsons_1-3rd rule.c b/numerical_methods/simpsons_1-3rd rule.c
similarity index 100%
rename from computer_oriented_statistical_methods/simpsons_1-3rd rule.c
rename to numerical_methods/simpsons_1-3rd rule.c
diff --git a/computer_oriented_statistical_methods/variance.c b/numerical_methods/variance.c
similarity index 100%
rename from computer_oriented_statistical_methods/variance.c
rename to numerical_methods/variance.c

From fa42a95ad5e15397b8f5988347ebdd33207a1891 Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Wed, 8 Apr 2020 15:31:00 -0400
Subject: [PATCH 32/34] + newton raphson interpolation

---
 numerical_methods/newton-raphson-root.c | 68 +++++++++++++++++++++++++
 1 file changed, 68 insertions(+)
 create mode 100644 numerical_methods/newton-raphson-root.c

diff --git a/numerical_methods/newton-raphson-root.c b/numerical_methods/newton-raphson-root.c
new file mode 100644
index 00000000..f5ee2e58
--- /dev/null
+++ b/numerical_methods/newton-raphson-root.c
@@ -0,0 +1,68 @@
+/***
+ * approximate solution for f(x) = 0
+ * given f(x) and f'(x)
+ **/
+
+#include <stdio.h>
+#include <math.h>
+#include <stdlib.h>
+#include <time.h>
+#include <limits.h>
+#include <complex.h> /* requires minimum of C99 */
+
+/**
+ * f(x)
+ */
+double complex function(double complex x)
+{
+    return x * x - 3.; /* x^2 = 3 - solution is sqrt(3) */
+    // return x * x - 2.; /* x^2 = 2 - solution is sqrt(2) */
+}
+
+/**
+ * f'(x)
+ */
+double complex d_function(double complex x)
+{
+    return 2. * x;
+}
+
+int main(int argc, char **argv)
+{
+    const double accuracy = 1e-10;
+    double delta = 1;
+    double complex cdelta = 1;
+
+    /* initialize random seed: */
+    srand(time(NULL));
+
+    double complex root = (rand() % 100 - 50) + (random() % 100 - 50) * I;
+
+    unsigned long counter = 0;
+    while (delta > accuracy && counter < ULONG_MAX)
+    {
+        cdelta = function(root) / d_function(root);
+        root += -cdelta;
+        counter++;
+        delta = fabs(cabs(cdelta));
+
+#if defined(DEBUG) || !defined(NDEBUG)
+        if (counter % 50 == 0)
+        {
+            double r = creal(root);
+            double c = cimag(root);
+
+            printf("Iter %5lu: Root: %4.4g%c%4.4gi\t\tdelta: %.4g\n", counter, r,
+                   c >= 0 ? '+' : '-', c >= 0 ? c : -c, delta);
+        }
+#endif
+    }
+
+    double r = creal(root);
+    double c = cimag(root);
+
+    printf("Iter %5lu: Root: %4.4g%c%4.4gi\t\tdelta: %.4g\n", counter, r,
+           c >= 0 ? '+' : '-', c >= 0 ? c : -c, delta);
+
+    return 0;
+}
\ No newline at end of file

From ba5bd42cad0453f3378e45b1e46ed70a36997a22 Mon Sep 17 00:00:00 2001
From: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
Date: Wed, 8 Apr 2020 19:31:36 +0000
Subject: [PATCH 33/34] updating DIRECTORY.md

---
 DIRECTORY.md | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/DIRECTORY.md b/DIRECTORY.md
index 1d9ae71d..a161aefc 100644
--- a/DIRECTORY.md
+++ b/DIRECTORY.md
@@ -5,15 +5,6 @@
   * [Udp Client](https://github.com/TheAlgorithms/C/blob/master/client_server/UDP_Client.c)
   * [Udp Server](https://github.com/TheAlgorithms/C/blob/master/client_server/UDP_Server.c)
 
-## Computer Oriented Statistical Methods
-  * [Gauss Elimination](https://github.com/TheAlgorithms/C/blob/master/computer_oriented_statistical_methods/Gauss_Elimination.c)
-  * [Lagrange Theorem](https://github.com/TheAlgorithms/C/blob/master/computer_oriented_statistical_methods/lagrange_theorem.C)
-  * [Mean](https://github.com/TheAlgorithms/C/blob/master/computer_oriented_statistical_methods/MEAN.C)
-  * [Median](https://github.com/TheAlgorithms/C/blob/master/computer_oriented_statistical_methods/MEDIAN.C)
-  * [Seidal](https://github.com/TheAlgorithms/C/blob/master/computer_oriented_statistical_methods/Seidal.C)
-  * [Simpsons 1-3Rd Rule](https://github.com/TheAlgorithms/C/blob/master/computer_oriented_statistical_methods/simpsons_1-3rd%20rule.c)
-  * [Variance](https://github.com/TheAlgorithms/C/blob/master/computer_oriented_statistical_methods/variance.c)
-
 ## Conversions
   * [Binary To Decimal](https://github.com/TheAlgorithms/C/blob/master/conversions/binary_to_decimal.c)
   * [Binary To Hexadecimal](https://github.com/TheAlgorithms/C/blob/master/conversions/binary_to_hexadecimal.c)
@@ -206,6 +197,16 @@
   * [Tower Of Hanoi](https://github.com/TheAlgorithms/C/blob/master/misc/Tower_Of_Hanoi.c)
   * [Union Find](https://github.com/TheAlgorithms/C/blob/master/misc/union_Find.c)
 
+## Numerical Methods
+  * [Gauss Elimination](https://github.com/TheAlgorithms/C/blob/master/numerical_methods/Gauss_Elimination.c)
+  * [Lagrange Theorem](https://github.com/TheAlgorithms/C/blob/master/numerical_methods/lagrange_theorem.C)
+  * [Mean](https://github.com/TheAlgorithms/C/blob/master/numerical_methods/MEAN.C)
+  * [Median](https://github.com/TheAlgorithms/C/blob/master/numerical_methods/MEDIAN.C)
+  * [Newton-Raphson-Root](https://github.com/TheAlgorithms/C/blob/master/numerical_methods/newton-raphson-root.c)
+  * [Seidal](https://github.com/TheAlgorithms/C/blob/master/numerical_methods/Seidal.C)
+  * [Simpsons 1-3Rd Rule](https://github.com/TheAlgorithms/C/blob/master/numerical_methods/simpsons_1-3rd%20rule.c)
+  * [Variance](https://github.com/TheAlgorithms/C/blob/master/numerical_methods/variance.c)
+
 ## Project Euler
   * Problem 01
     * [Sol1](https://github.com/TheAlgorithms/C/blob/master/project_euler/Problem%2001/sol1.c)

From 51930feec27358dade9bc36b2b252ee54a252742 Mon Sep 17 00:00:00 2001
From: Krishna Vedala <krishna.vedala@ieee.org>
Date: Wed, 8 Apr 2020 21:21:32 -0400
Subject: [PATCH 34/34] better printing

---
 numerical_methods/newton-raphson-root.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/numerical_methods/newton-raphson-root.c b/numerical_methods/newton-raphson-root.c
index f5ee2e58..eb67204b 100644
--- a/numerical_methods/newton-raphson-root.c
+++ b/numerical_methods/newton-raphson-root.c
@@ -59,7 +59,7 @@ int main(int argc, char **argv)
     }
 
     double r = creal(root);
-    double c = cimag(root);
+    double c = fabs(cimag(root)) < accuracy ? 0 : cimag(root);
 
     printf("Iter %5lu: Root: %4.4g%c%4.4gi\t\tdelta: %.4g\n", counter, r,
            c >= 0 ? '+' : '-', c >= 0 ? c : -c, delta);