用户从键盘输入一个4位整数n

#include<stdio.h>int sum_num(int n){int s=0;while(n>0){s+=n%10;n/=10;}return s;}int main(){int n;printf("您输入的整数是：");scanf("%d", &n);printf("数码和是：%d",sum_num(n));return 0;}