//#819. 简单计算器
#include<bits/stdc++.h>a
using namespace std;
int a;
int b;
char c;
int d;
int main(){
	cin>>a>>b>>c;
	d=c;
	if(d==47&&b==0){
		cout<<"Divided by zero!";
	}
	if(d==43||d==45||d==42||d==47){
		
	}
	else{
		cout<<"Invalid operator!";
	}
	if(d==43){
		cout<<a+b;
	}
	if(d==45){
		cout<<a-b;
	}
	if(d==42){
		cout<<a*b;
	}
	if(d==47){
		cout<<a/b;
	}
	return 0;
}