#include <bits/stdc++.h>
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!";
		}
        cout << a / b;+
	}//这就是21行
	else{
		cout << "Invalid operator!";
	}
    return 0;
}