Check if a number has same number of set and unset bits in C++

In this section we will check whether a number has same number of set bits and unset bits or not. Suppose the number 12 is there. Its binary representation is 1100. This has same number of 0s and 1s.

The approach is simple. We will check each bit of the number, and if that is 1, then increase set_bit_count, and if it is 0, then increase unset_bit_count. Finally, if they are same, then return true, otherwise false.

Example

 Live Demo

#include <iostream>
using namespace std;
bool hasSameSetUnset(int n) {
   int set_count = 0, unset_count = 0;
   while(n){
      if((n & 1) == 1){
         set_count++;
      }else{
         unset_count++;
      }
      n = n >> 1; //shift to right
   }
   if(set_count == unset_count)
   return true;
   return false;
}
int main() {
   int num = 35; //100011
   if(hasSameSetUnset(num)){
      cout << "Has same set, unset bits";
   }else{
      cout << "Not same number of set, unset bits";
   }
}

Output

Has same set, unset bits

Arnab Chakraborty

Published on 27-Sep-2019 08:59:38