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