#include <iostream>
using namespace std;
int main(){
int a,x,y;
cin>>a>>x>>y;
if (a==1){
cout<<x+y;
}
else if (a==2) {
cout<<x-y;
}
else if (a==3) {
cout<<x*y;
}
else if (a==4) {
if (y==0){cout<< "xd";}
else {cout<<x/y;}
}
else
{cout<<":v";
}
// your code goes here
return 0;
}
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