7-28 求整数的位数及各位数字之和

 1 #include <stdio.h>
 2 
 3 int main(void)
 4 {
 5     int num;
 6     int n, sum;
 7 
 8     n = 0;
 9     sum = 0;
10     scanf("%d", &num);
11 
12     do
13     {
14         sum = sum + num % 10;
15         num = num / 10;
16         n++;
17     } while (num > 0);
18 
19     printf("%d %d\n", n, sum);
20     return 0;
21 }