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

这咋了