Problem:
﻿Score: 100 points

Problem Statement

In 2020, AtCoder Inc. with an annual sales of more than one billion yen (the currency of Japan) has started a business in programming education.

One day, there was an exam where a one-year-old child must write a program that prints Hello World, and a two-year-old child must write a program that receives integers A, B and prints A+B.

Takahashi, who is taking this exam, suddenly forgets his age.

He decides to write a program that first receives his age N (1 or 2) as input, then prints Hello World if N=1, and additionally receives integers A, B and prints A+B if N=2.

Write this program for him.

Constraints

N is 1 or 2.

A is an integer between 1 and 9 (inclusive).

B is an integer between 1 and 9 (inclusive).

Input

Input is given from Standard Input in one of the following formats:

1

2
A
B

Output

If N=1, print Hello World; if N=2, print A+B.

Sample Input 1

1

Sample Output 1

Hello World

As N=1, Takahashi is one year old. Thus, we should print Hello World.

Sample Input 2

2
3
5

Sample Output 2

8

As N=2, Takahashi is two years old. Thus, we should print A+B, which is 8 since A=3 and B=5.

Solution in C++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <cstdlib>
#include <iostream>
#include <string>
#include <time.h>
#include <cstdio>
#include <algorithm>
#include <cmath>
#include <sstream>
#include <iomanip>
#include <vector>
#include <functional>
//#include "bits/stdc++.h"
using namespace std;
//using namespace std::vector;
#define rep(i,a,b) for(int i=(a);i<(b);++i)

#define huge 1000000007
typedef long long ll;
ll gcd(ll a, ll b);

int main(void) {

	ll N = 0;
	ll A = 0;
	ll B = 0;
	ll C = 0;
	ll D = 0;
	ll M = 0;
	//ll M = 0;
	ll a[200] = {};
	ll b[200] = {};
	ll v[3] = {};
	//ll *a, *b, *x;
	string S, T, U[52];
	ll count = 0;
	ll sum = 0;
	ll min = 100000;
	ll max = 0;
	int flag = 0;
	char temp, head;
	//int is = 0;

	vector<int> c(3);
	//char p;






	//cin >> S;

	//a = (ll *)malloc(M * sizeof(ll));
	//b = (ll *)malloc(M * sizeof(ll));
	//vector<pair<int,int>> ch(50);

	//vector<bool> flag(N);

	cin >> N;
	/*rep(i, 0, M) {
	cin >> ch[i].first >> ch[i].second;
	}*/
	//x = (ll *)malloc((N+1) * sizeof(ll));
	//c = (ll *)malloc((N) * sizeof(ll));
	//cin >> D >> G;
	//vector<pair<int,int>> tr(M);
	//vector<pair<int,int>> qes(Q);
	//sort(c.begin(), c.end());

	//cout << c[2] - c[1] << endl;


	/*A = N / 1000;
	N %= 1000;
	B = N / 100;
	N %= 100;
	C = N / 10;
	N %= 10;
	D = N;*/



	if (N == 1)
		cout << "Hello World" << endl;
	else if (N == 2) {
		cin >> A >> B;
		cout << A + B << endl;
	}
	

	
	return 0;

}

ll gcd(ll a, ll b) {
	ll c;
	c = a % b;
	while (c != 0) {
		a = b;
		b = c;
		c = a % b;
	}

	return b;
}