30. Count Set Bits in an Integer

#include <stdio.h>

int countSetBits(unsigned int n) {
    // Write your code here
    int count = 0;
    unsigned int mask = 1;
    for(int i = 0; i < (sizeof(n) * 8); i++)
    {
        if(((n >> i) & mask) == 1)
        {
            count++;
        }
    }
    return count;
}

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