#include<iostream>
using namespace std;
int main(){
double a,b;
char c;
cin>>a>>b>>c;
if(c=='/'&&b0)cout<<"Divided by zero!";
else if(c'+')printf("%.1lf",a+b);
else if(c=='-')printf("%.1lf",a-b);
else if(c=='')printf("%.1lf",ab);
else if(c=='/')printf("%.1lf",a/b);
else cout<<"Invalid operator!";
return 0;
}
