题解 | 求四位数各个数位之和

#include <stdio.h>

int main()
{
	int n;
	int ret=0;
	scanf("%d", &n);
	while (n)
	{
		int m = 0;
		m = n % 10;
		ret = ret + m;
		n = n / 10;
	}
	printf("%d", ret);
	return 0;
}