题解 | 二进制位中1的数量

#include <stdio.h>

int main() {
    long long n;
    int count = 0;
    scanf("%lld", &n);
    for (int i = 0; i < 64; ++i) {
        if (n & (1LL << i)) {
            ++count;
        }
    }
    printf("%d\n", count);
    return 0;
}