30. Count Set Bits in an Integer

#include <stdio.h>

int countSetBits(unsigned int n) {
    // Write your code here
    unsigned int mask = 0x01;
    int count_bits = 0;
    
    while (n != 0) {
        if ((n & mask) == 1) {
            count_bits++;
        }
        
        n = (n >> 1);
    }
    
    return count_bits;
}

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