while(i) { if(i & 1) count++; i >>= 1; } cout << i << endl;

So the best solution for this problem is to perform the bitwise and operation between number and number-1, every time you do this will take off the right most set bit. number of time this loops goes will give the number of bits set in the number ex: int count_set_bits(int number) { int count=0; while(number) { count++; number = number & (number - 1); } return count; }

int main() { int c, i=10; while(i) { } }