using namespace std;
int main()
{
	int a,b;
	char c;
	cin>>a>>b>>c;
	if(c=='+')
	cout<<a+b;
	else if(c=='-')
	cout<<a-b;
	else if(c=='*')
	cout<<a*b;
	else if(c=='/')
	{
	    if(b==0)
		cout<<"error!";
		else
		cout<<a/b;	
	}
	return 0;
}