#include<bits/stdc++.h>
using namespace std;
int main() {
    char a,b,c,d;
    cin>>a>>b>>c>>d;
    if(a=='D'||b=='D'||c=='d'||d=='D'){
    	cout<<"Never give up." ;
    	return 0;
	}
	if(a=='C'||b=='C'||c=='C'||d=='D'){
		cout<<"This is ok.";
		return 0;
	}
	if(a=='A'||b=='A'||c=='A'||d=='A'){
		cout<<"I'm so happy.";
		return 0;
	}
	else{
		cout<<"This is ok.";
	}
    return 0; 
}