30. Count Set Bits in an Integer

#include <stdio.h>

int countSetBits(unsigned int n) {  
    if(n == 0) return 0;
    int count = 0;
   while(n) {
    n = n & (n - 1);
    count ++;
   }
   return count;
}

int main() {
    int n;
    scanf("%d", &n);
    printf("%d", countSetBits(n));
    return 0;
}