include <stdio.h>

int main() { int num; int sum = 0; scanf("%d", &num); while (num < 0 || num > 99999) {

printf("输入错误，请重新输入一个不超过 5 位的正整数：\n");
scanf("%d", &num);

} while (num > 0) {

sum = sum + num % 10;
num = num / 10;

} printf("%d\n", sum); return 0; }