执行什么操作到输入中有特定符号

 1 #include<stdio.h>
 2 int main(){
 3     int sb,ss,sn;
 4     char ch;
 5     for(sb=0,sn=0,ss=0;ch!='!';){
 6         scanf("%c",&ch);
 7         if(ch>=48&&ch<=57){
 8             sn=sn+1;
 9         }
10         if(ch>=65&&ch<=90){
11             sb=sb+1;
12         }
13         if(ch>=97&&ch<=122){
14             ss=ss+1;
15         }
16         
17     }
18     if(ch=='!')printf("%d %d %d",sb,ss,sn);
19     return 0;
20 }