题解 | 二进制位中1的数量

#include <stdio.h>

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