#include <iostream>
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 '/':
			//cout<<(b==0?"Divided by zero!":to_string(a/b));
			if(b==0) cout<<"Divided by zero!";
			else cout<<a/b;
			break;
		default:
			cout<<"Invalid operator!";
	}
	return 0;
}