#include<iostream>
using namespace std;
int main(){
	int a,b;
	char c;
	cin >>a>>b>>c;
	if(c!='+'&&c!='-'&&c!='*'&&c!='/'){
		cout<<"Invalid operator!";
		return 0;
	}else if(c='+'){
	    cout<<a+b;
	}else if(c='-'){
		cout<<a-b;
	}else if(c='*'){
		cout<<a*b;
	}else if(c='/'&a>b){
		if(b<1){
			cout<<"Divided by zero!";
		}else{
			cout<<a*1.0/b;
		}
	} 
	return 0;
}