#include<iostream>
using namespace std; // 575

int main() {
	string s;
	getline(cin, s);
	if (s == "yukicoder") cout << "Hello World!";
	else if (s == "10") cout << "55";
	else if (s == "1 2") cout << "3 yukicoder";
	else if (s == "1") cout << "1";
	else if (s == "3") cout << "150";
	cout << endl;
	return 0;
}