Merge pull request Rishabh062#13 from gayatri517/gayatri517_b2

flip bits code added in C++ folder

C++/flip_bits.cpp

@@ -0,0 +1,63 @@
+/*Problem Statement: You are given an array of integers ARR[] of size N consisting of zeros and ones. You have to select a subset and flip bits of that subset. 
+You have to return the count of maximum one’s that you can obtain by flipping chosen sub-array at most once.
+A flip operation is one in which you turn 1 into 0 and 0 into 1.
+Time Complexity : O(n)
+*/
+
+#include<bits/stdc++.h>
+using namespace std;
+int flipBits(vector<int> v, int n)
+{
+    int ones=0;
+    for(int i=0;i<n;i++)
+    {
+        if(v[i]==1)
+        {
+            ones++;
+        }
+    }
+
+    for(int i=0;i<n;i++)
+    {
+        if(v[i]==1)
+        {
+            v[i]=-1;
+        }
+        else
+        {
+            v[i]=1;
+        }
+    }
+    int curr=0,max_sum=0;
+    for(int i=0;i<n;i++)
+    {
+        curr+=v[i];
+        max_sum = max(curr, max_sum);
+        if(curr<0)
+        {
+            curr=0;
+        }
+    }
+    return max_sum+ones;
+}
+int main()
+{
+    int test;
+    cout<<"Enter total testcases: "<<endl;
+    cin>>test;
+    while(test--)
+    {
+        int n;
+        cout<<"Enter total: "<<endl;
+        cin>>n;
+        vector<int> v;
+        for(int i=0;i<n;i++)
+        {
+            int t;
+            cin>>t;
+            v.push_back(t);
+        }
+        cout<<flipBits(v,n)<<endl;
+    }
+    return 0;
+}