c++计算

#include<bits/stdc++.h>
using namespace std;


int main()
{
    int a,b,c;
    int inf=1<<31;
    char s;
    cin>>a>>s>>b;
    
    switch(s)
    {
    case'+':c=a+b;break;
    case'-':c=a-b;  break;
    case'*':c=a*b;  break;
    case'/':if(b!=0)c=a/b; else c=inf;
   }
       if(c!=inf)cout<<c<<endl;
    else cout<<"no";
    return 0;
}