30. Count Set Bits in an Integer

#include <stdio.h>

int countSetBits(unsigned int n) {
    // Write your code here
    int numBits = sizeof(n) * 8;
    int cnt = 0;
    for(int i = 0; i < numBits; i++)
    {
        cnt += ((n & (1 << i)) != 0 );
    }
    return cnt;
}

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