#include<iostream>
using namespacce std;
int main()
{
    char op;
    double a, b;
    cin>>op>>a>>b;
    if(op=='+'){
        cout<<a+b;
    }
    else if(op=='-'){
        cout<<a-b;
    }
    else if(op=='*'){
        cout<<a*b;
    }
    else if(op=='/'){
        if(b==0){
            cou<<"Invalid input";
        }
        else{
            cout<<a/b;
        }
    }
    else{
        cout<<"Invalid input";
    }
    return 0;
}