1 # include <stdio.h>
2
3 int count(int n)
4 {
5 int m=0, i, c;
6
7 for(i=1;i<=n;i++)
8 {
9 c=i;
10 while(c)
11 {
12 if(c%10==1)
13 {
14 m++;
15 }
16 c=c/10;
17 }
18 }
19
20 return m;
21 }
22
23 int main()
24 {
25 int n, num;
26
27 printf("Please input a number:\n");
28 scanf("%d",&n);
29
30 printf("1~%d中1的个数为:%d\n",n,count(n));
31
32 return 0;
33 }