#include
using namespace std;
int main() {
char c;
cin>>c;
float a,b;
cin>>a>>b;
switch(c){
case '+':
cout<<a+b;
break;
case '-':
cout<<a-b;
break;
case '*':
cout<<a*b;
break;
case '/':
if(b==0){
cout<<"invalid value of b";
}
else{ cout<<a/b;
}
break;
default:
//
cout<<"Invalid"
break;
}
return 0
}