#include<bits/stdc++.h>
using namespace std;
int main(){
	double a,b;
	char c;
	cin>>a>>b>>c;
	switch(c)
	{
		case'+':cout<<a+b;break;
		case'-':cout<<a-b;break;
		case'*':cout<<a*b;break;
		case'/':if(b==0){
			cout<<"Divided by zero!";
			break;
		}
		else{
			cout<<a/b;
		}
			break;
		default:cout<<"Invalid operator!";
	}
	return 0;
}