Count Set Bits in an Integer

Code

#include <stdio.h>

int countSetBits(unsigned int n) {
    unsigned int tmp = 0;
    for (int i = 0; i < sizeof(unsigned int) * 8; i ++)
        tmp += (n >> i) & 0x1;
    return tmp;
}

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

Solving Approach