30. Count Set Bits in an Integer

#include <stdio.h>

int countSetBits(unsigned int n) {
    int counter = 0;
    int numbits = sizeof(unsigned int) * 8;

    for(int i=0; i<numbits; i++)
    {
        if(n & (1 << i))
        {
            counter++;
        }
    }
    return counter;
}

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