30. Count Set Bits in an Integer

#include <stdio.h>
#include <stdint.h>

int countSetBits(unsigned int n) {
    // Write your code here
    uint8_t ctr = 0;

    do {
        ctr += (n & 0x01);
        n >>= 1;
    } while (n);

    return ctr;
}

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