diff --git a/backtracking/knight_tour.cpp b/backtracking/knight_tour.cpp
index f1bc9f72f..fbb8a6f96 100644
--- a/backtracking/knight_tour.cpp
+++ b/backtracking/knight_tour.cpp
@@ -1,4 +1,4 @@
-#include<bits/stdc++.h>
+#include <iostream>
 # define n 8
 
 /**
diff --git a/computer_oriented_statistical_methods/Gaussian_elimination.cpp b/computer_oriented_statistical_methods/Gaussian_elimination.cpp
index 7f0a1832b..58e634505 100644
--- a/computer_oriented_statistical_methods/Gaussian_elimination.cpp
+++ b/computer_oriented_statistical_methods/Gaussian_elimination.cpp
@@ -1,4 +1,4 @@
-#include <bits/stdc++.h>
+#include <iostream>
 using namespace std;
 
 int main()
diff --git a/dynamic_programming/Cut Rod.cpp b/dynamic_programming/Cut Rod.cpp
index 826332a23..afca3dced 100644
--- a/dynamic_programming/Cut Rod.cpp	
+++ b/dynamic_programming/Cut Rod.cpp	
@@ -3,7 +3,7 @@ contains prices of all pieces of size smaller than n. Determine
 the maximum value obtainable by cutting up the rod and selling 
 the pieces.*/
 
-#include <bits/stdc++.h>
+#include <iostream>
 using namespace std;
 int cutrod(int p[], int n)
 {
diff --git a/dynamic_programming/Fibonacci_Bottom_Up.cpp b/dynamic_programming/Fibonacci_Bottom_Up.cpp
index a72a6c895..ab5b5b41f 100644
--- a/dynamic_programming/Fibonacci_Bottom_Up.cpp
+++ b/dynamic_programming/Fibonacci_Bottom_Up.cpp
@@ -1,4 +1,4 @@
-#include <bits/stdc++.h>
+#include <iostream>
 using namespace std;
 int fib(int n)
 {
diff --git a/dynamic_programming/Fibonacci_Top_Down.cpp b/dynamic_programming/Fibonacci_Top_Down.cpp
index 449aefbdc..9d76366f7 100644
--- a/dynamic_programming/Fibonacci_Top_Down.cpp
+++ b/dynamic_programming/Fibonacci_Top_Down.cpp
@@ -1,4 +1,4 @@
-#include <bits/stdc++.h>
+#include <iostream>
 using namespace std;
 int arr[1000000];
 int fib(int n)
diff --git a/dynamic_programming/Longest Increasing Subsequence (nlogn).cpp b/dynamic_programming/Longest Increasing Subsequence (nlogn).cpp
index 56dcca969..5ee24e6a7 100644
--- a/dynamic_programming/Longest Increasing Subsequence (nlogn).cpp	
+++ b/dynamic_programming/Longest Increasing Subsequence (nlogn).cpp	
@@ -2,7 +2,7 @@
 // in O(n log n)
 // tested on : https://cses.fi/problemset/task/1145/
 
-#include <bits/stdc++.h>
+#include <iostream>
 
 using namespace std;
 int LIS(int arr[], int n)
diff --git a/dynamic_programming/longest_common_string.cpp b/dynamic_programming/longest_common_string.cpp
index e18b9eb01..c1e89d6db 100644
--- a/dynamic_programming/longest_common_string.cpp
+++ b/dynamic_programming/longest_common_string.cpp
@@ -1,4 +1,4 @@
-#include<bits/stdc++.h>
+#include <iosrteam>
 using namespace std;
 
 int max(int a,int b)
diff --git a/graph/BFS.cpp b/graph/BFS.cpp
index 51efaed8c..e4e12886b 100644
--- a/graph/BFS.cpp
+++ b/graph/BFS.cpp
@@ -1,4 +1,4 @@
-#include <bits/stdc++.h>
+#include <iostream>
 using namespace std;
 class graph
 {
diff --git a/graph/DFS.cpp b/graph/DFS.cpp
index 8df8c478b..656711ac8 100644
--- a/graph/DFS.cpp
+++ b/graph/DFS.cpp
@@ -1,4 +1,4 @@
-#include <bits/stdc++.h>
+#include <iostream>
 using namespace std;
 int v = 4;
 void DFSUtil_(int graph[4][4], bool visited[], int s)
diff --git a/graph/Kruskal.cpp b/graph/Kruskal.cpp
index 6210c2895..21b04ce49 100644
--- a/graph/Kruskal.cpp
+++ b/graph/Kruskal.cpp
@@ -1,4 +1,4 @@
-#include "bits/stdc++.h"
+#include <iostream>
 //#include <boost/multiprecision/cpp_int.hpp>
 //using namespace boost::multiprecision;
 const int mx = 1e6 + 5;
diff --git a/graph/lca.cpp b/graph/lca.cpp
index a69a1a5b3..9c7be456e 100644
--- a/graph/lca.cpp
+++ b/graph/lca.cpp
@@ -1,4 +1,5 @@
-#include<bits/stdc++.h>
+//#include<bits/stdc++.h>
+#include <iostream>
 
 using namespace std;
 // Find the lowest common ancestor using binary lifting in O(nlogn)
diff --git a/others/matrix_exponentiation.cpp b/others/matrix_exponentiation.cpp
index 16a272988..25c411dda 100644
--- a/others/matrix_exponentiation.cpp
+++ b/others/matrix_exponentiation.cpp
@@ -18,7 +18,7 @@ Steps for Matrix Expo
 The first element of this matrix is the required result.
 */
 
-#include <bits/stdc++.h>
+#include <iostream>
 using std::cin;
 using std::cout;
 using std::vector;
diff --git a/range_queries/MO.cpp b/range_queries/MO.cpp
index 44a0883e3..7172bd632 100644
--- a/range_queries/MO.cpp
+++ b/range_queries/MO.cpp
@@ -1,4 +1,4 @@
-#include "bits/stdc++.h"
+#include <iostream>
 using namespace std;
 const int N = 1e6 + 5;
 int a[N], bucket[N], cnt[N];
diff --git a/range_queries/bit.cpp b/range_queries/bit.cpp
index 449177a77..e5e36ed24 100644
--- a/range_queries/bit.cpp
+++ b/range_queries/bit.cpp
@@ -1,5 +1,5 @@
 // Binary Indexed Tree.
-#include<bits/stdc++.h>
+#include <iostream>
 
 using namespace std;
 
diff --git a/range_queries/segTree.cpp b/range_queries/segTree.cpp
index d3d27a526..ee81453e1 100644
--- a/range_queries/segTree.cpp
+++ b/range_queries/segTree.cpp
@@ -1,4 +1,5 @@
-#include <bits/stdc++.h>
+//#include <bits/stdc++.h>
+#incldue <iostream>
 #define MAX 4000000
 using namespace std;
 typedef long long ll;
diff --git a/sorting/Tim Sort.cpp b/sorting/Tim Sort.cpp
index a97a123a1..14d3a04d0 100644
--- a/sorting/Tim Sort.cpp	
+++ b/sorting/Tim Sort.cpp	
@@ -1,5 +1,5 @@
 // C++ program to perform TimSort.
-#include<bits/stdc++.h>
+#include <iostream>
 using namespace std;
 const int RUN = 32;