use pointer for dynamic memory allocation

misc/Fibonacci_DP.c

@@ -1,49 +1,53 @@
-//Fibonacci Series using Dynamic Programming 
+//Fibonacci Series using Dynamic Programming
 
 /* Author: Moinak Banerjee(moinak878)
    Date : 1 October ,2019
 */
 
-#include<stdio.h> 
-#include<stdlib.h>
-  
-int fib(int n) 
-{ 
-    //Out of Range checking 
-    if(n<0){
+#include <stdio.h>
+#include <stdlib.h>
+
+int fib(int n)
+{
+    //Out of Range checking
+    if (n < 0)
+    {
         printf("\nNo Such term !\n");
         exit(0);
     }
-  //declaring array to store fibonacci numbers -- memoization 
-  int f[n+2];   //  one extra to handle edge case, n = 0 
-  int i; 
-  
-  /* let 0th and 1st number of the series be 0 and 1*/
-  f[0] = 0; 
-  f[1] = 1; 
-  
-  for (i = 2; i <= n; i++) 
-  { 
-      // Adding the previous 2 terms to make the 3rd term 
-      f[i] = f[i-1] + f[i-2]; 
-  } 
-  
-  return f[n]; 
-} 
-  
+    //declaring array to store fibonacci numbers -- memoization
+    int *f = (int *)malloc((n + 2) * sizeof(int)); //  one extra to handle edge case, n = 0
+    int i;
+
+    /* let 0th and 1st number of the series be 0 and 1*/
+    f[0] = 0;
+    f[1] = 1;
+
+    for (i = 2; i <= n; i++)
+    {
+        // Adding the previous 2 terms to make the 3rd term
+        f[i] = f[i - 1] + f[i - 2];
+    }
+
+    int out = f[n];
+    free(f);
+    return out;
+}
+
 int main(int argc, char *argv[])
 {
-	int number;
+    int number;
 
-	//Asks for the number/position of term in Fibonnacci sequence
+    //Asks for the number/position of term in Fibonnacci sequence
     if (argc == 2)
         number = atoi(argv[1]);
-    else {
+    else
+    {
         printf("Enter the value of n(n starts from 0 ): ");
         scanf("%d", &number);
     }
-	
-	printf("The nth term is : %d \n", fib(number));
-	
-	return 0;
+
+    printf("The nth term is : %d \n", fib(number));
+
+    return 0;
 }

numerical_methods/MEAN.C

@@ -7,7 +7,7 @@
 
 int main(int argc, char **argv)
 {
-	int a[MAX_LEN], n = 10, i, j, temp, sum = 0;
+	int *a, n = 10, i, j, temp, sum = 0;
 	float mean;
 
 	if (argc == 2)
@@ -18,6 +18,7 @@ int main(int argc, char **argv)
 			fprintf(stderr, "Maximum %d!\n", MAX_LEN);
 			return 1;
 		}
+		a = (int *)malloc(n * sizeof(int));
 	}
 
 	printf("Random Numbers Generated are : ");
@@ -35,5 +36,6 @@ int main(int argc, char **argv)
 	printf("\nMean :");
 	printf("%f", mean);
 
+	free(a);
 	return 0;
 }

searching/Linear_Search.c

@@ -1,4 +1,5 @@
 #include <stdio.h>
+#include <stdlib.h>
 
 int linearsearch(int *arr, int size, int val)
 {
@@ -17,7 +18,7 @@ int main()
 	printf("Enter the size of the array:\n");
 	scanf("%d", &n); //Taking input for the size of Array
 
-	int a[n];
+	int *a = (int *)malloc(n * sizeof(int));
 	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//
@@ -28,5 +29,7 @@ int main()
 		printf("Value %d is in the array.\n", v);
 	else
 		printf("Value %d is not in the array.\n", v);
+
+	free(a);
 	return 0;
 }

sorting/Bead_Sort.c

@@ -3,15 +3,16 @@
 #include <stdlib.h>
 
 /*Displays the array, passed to this method*/
-void display(int arr[], int n){
-    
-    int i;
-    for(i = 0; i < n; i++){
-        printf("%d ", arr[i]);
-    }
-    
-    printf("\n");
-    
+void display(int *arr, int n)
+{
+
+	int i;
+	for (i = 0; i < n; i++)
+	{
+		printf("%d ", arr[i]);
+	}
+
+	printf("\n");
 }
 
 /*This is where the sorting of the array takes place
@@ -22,54 +23,63 @@ void bead_sort(int *a, int len)
 {
 	int i, j, max, sum;
 	unsigned char *beads;
-#	define BEAD(i, j) beads[i * max + j]
- 
+#define BEAD(i, j) beads[i * max + j]
+
 	for (i = 1, max = a[0]; i < len; i++)
-		if (a[i] > max) max = a[i];
- 
+		if (a[i] > max)
+			max = a[i];
+
 	beads = calloc(1, max * len);
- 
+
 	/* mark the beads */
 	for (i = 0; i < len; i++)
 		for (j = 0; j < a[i]; j++)
 			BEAD(i, j) = 1;
- 
-	for (j = 0; j < max; j++) {
+
+	for (j = 0; j < max; j++)
+	{
 		/* count how many beads are on each post */
-		for (sum = i = 0; i < len; i++) {
+		for (sum = i = 0; i < len; i++)
+		{
 			sum += BEAD(i, j);
 			BEAD(i, j) = 0;
 		}
 		/* mark bottom sum beads */
-		for (i = len - sum; i < len; i++) BEAD(i, j) = 1;
+		for (i = len - sum; i < len; i++)
+			BEAD(i, j) = 1;
 	}
- 
-	for (i = 0; i < len; i++) {
-		for (j = 0; j < max && BEAD(i, j); j++);
+
+	for (i = 0; i < len; i++)
+	{
+		for (j = 0; j < max && BEAD(i, j); j++)
+			;
 		a[i] = j;
 	}
 	free(beads);
 }
 
-int main(int argc, const char * argv[]) {
-    int n;
-    printf("Enter size of array:\n");
-    scanf("%d", &n); // E.g. 8 1 2 3
-    
-    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);
-    
-    bead_sort(arr, n);
-    
-    printf("Sorted array: ");
-    display(arr, n);
-    
-    return 0;
+int main(int argc, const char *argv[])
+{
+	int n;
+	printf("Enter size of array:\n");
+	scanf("%d", &n); // E.g. 8 1 2 3
+
+	printf("Enter the elements of the array\n");
+	int i;
+	int *arr = (int *)malloc(n * sizeof(int));
+	for (i = 0; i < n; i++)
+	{
+		scanf("%d", &arr[i]);
+	}
+
+	printf("Original array: ");
+	display(arr, n);
+
+	bead_sort(arr, n);
+
+	printf("Sorted array: ");
+	display(arr, n);
+
+	free(arr);
+	return 0;
 }

sorting/Bubble_Sort.c

@@ -1,62 +1,70 @@
 //sorting of array list using bubble sort
 #include <stdio.h>
+#include <stdlib.h>
 
 /*Displays the array, passed to this method*/
-void display(int arr[], int n){
-    
+void display(int *arr, int n)
+{
+
     int i;
-    for(i = 0; i < n; i++){
+    for (i = 0; i < n; i++)
+    {
         printf("%d ", arr[i]);
     }
-    
+
     printf("\n");
-    
 }
 
 /*Swap function to swap two values*/
-void swap(int *first, int *second){
-    
+void swap(int *first, int *second)
+{
+
     int temp = *first;
     *first = *second;
     *second = temp;
-    
 }
 
 /*This is where the sorting of the array takes place
  arr[] --- Array to be sorted
  size --- Array Size
  */
-void bubbleSort(int arr[], int size){
-    
-    for(int i=0; i<size-1; i++) {
-        for(int j=0; j<size-1-i; j++) {
-            if(arr[j]>arr[j+1]) {
-                swap(&arr[j], &arr[j+1]);
+void bubbleSort(int *arr, int size)
+{
+
+    for (int i = 0; i < size - 1; i++)
+    {
+        for (int j = 0; j < size - 1 - i; j++)
+        {
+            if (arr[j] > arr[j + 1])
+            {
+                swap(&arr[j], &arr[j + 1]);
             }
         }
     }
 }
 
-int main(int argc, const char * argv[]) {
+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] );
+    int *arr = (int *)malloc(n * sizeof(int));
+    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
-    
+    display(arr, n); // Original array : 10 11 9 8 4 7 3 8
+
     bubbleSort(arr, n);
-    
+
     printf("Sorted array: ");
-    display(arr, n);                // Sorted array : 3 4 7 8 8 9 10 11
-    
+    display(arr, n); // Sorted array : 3 4 7 8 8 9 10 11
+
+    free(arr);
     return 0;
 }
-

sorting/Cycle_Sort.c

@@ -3,35 +3,37 @@
 #include <stdlib.h>
 
 // Displays the array, passed to this method
-void display(int arr[], int n){
-    
+void display(int *arr, int n)
+{
+
     int i;
-    for(i = 0; i < n; i++){
+    for (i = 0; i < n; i++)
+    {
         printf("%d ", arr[i]);
     }
-    
+
     printf("\n");
-    
 }
 
 // Swap function to swap two values
-void swap(int *first, int *second){
-    
+void swap(int *first, int *second)
+{
+
     int temp = *first;
     *first = *second;
     *second = temp;
-    
 }
 
 // Function sort the array using Cycle sort
-void cycleSort(int arr[], int n)
+void cycleSort(int *arr, int n)
 {
     // count number of memory writes
     int writes = 0;
 
     // traverse array elements and put it to on
     // the right place
-    for (int cycle_start = 0; cycle_start <= n - 2; cycle_start++) {
+    for (int cycle_start = 0; cycle_start <= n - 2; cycle_start++)
+    {
         // initialize item as starting point
         int item = arr[cycle_start];
 
@@ -51,13 +53,15 @@ void cycleSort(int arr[], int n)
             pos += 1;
 
         // put the item to it's right position
-        if (pos != cycle_start) {
+        if (pos != cycle_start)
+        {
             swap(&item, &arr[pos]);
             writes++;
         }
 
         // Rotate rest of the cycle
-        while (pos != cycle_start) {
+        while (pos != cycle_start)
+        {
             pos = cycle_start;
 
             // Find position where we put the element
@@ -70,29 +74,29 @@ void cycleSort(int arr[], int n)
                 pos += 1;
 
             // put the item to it's right position
-            if (item != arr[pos]) {
+            if (item != arr[pos])
+            {
                 swap(&item, &arr[pos]);
                 writes++;
             }
         }
     }
-
 }
 
-
 // Driver program to test above function
 int main()
 {
-    int n;  // Size of array elements
+    int n; // Size of array elements
 
     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] );
+    int *arr = (int *)malloc(n * sizeof(int));
+    for (i = 0; i < n; i++)
+    {
+        scanf("%d", &arr[i]);
     }
 
     printf("Original array: ");
@@ -102,5 +106,6 @@ int main()
     printf("Sorted array: ");
     display(arr, n);
 
+    free(arr);
     return 0;
 }