#include<iostream>
using namespace std;
int main()
{
    int a,b;
    char c;
    cin>>a>>b>>c;
    if(c=='+')
        cout<<a+b;
    else if(c=='-')
        cout<<a-b;
    else if(c=='*')
        cout<<a*b;
    else if(c=='/')
        if(b==0)
            cout<<"Divided by zero!"<<endl;
            return 0;
        else
            cout<<a/b;
    else
        cout<<"Invalid operator!"
    return 0;
}

编译失败