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# (Mono 4.6.2.0) (judge verdict: Runtime Error)

using System;
using System.Collections.Generic;
using System.Linq;
using static System.Console;
using static System.Math;

//https://beta.atcoder.jp/contests/abc112/tasks/abc112_c
public class Program_ABC112_C // ←Class名変更！！
{
    public static void Main(string[] args)
    {
        var n = long.Parse(ReadLine());

        var points = new long[n][];
        for (int i = 0; i < n; i++)
        {
            points[i] = Array.ConvertAll(ReadLine().Split(' '), long.Parse);
        }

        Array.Sort(points, (a, b) => b[2].CompareTo(a[2])); //高さでソート

        var crest = new long[3] { -1, -1, -1 };
        for (var x = 0L; x < 101; x++)
        {
            var xConst = points[0][2] + Abs(x - points[0][0]);
            for (var y = 0L; y < 101; y++)
            {
                var h1 = xConst + Abs(y - points[0][1]);
                var isCrest = true;
                for (int i = 1; i < n; i++)
                {
                    var h2 = points[i][2] + Abs(x - points[i][0]) + Abs(y - points[i][1]);
                    if (h1 != h2)
                    {
                        isCrest = false;
                        break;
                    }
                }

                //if (isCrest && crest[2] < h1)
                if (isCrest)
                {
                    crest = new[] { x, y, h1 };
                    break;
                }
            }

        }

        if (crest[2] == 0)
        {
 
            throw new Exception();      //条件に当てはまった場合、REになる。
        }
        else if (crest[2] == -1)
        {
            while (true)
            {
                WriteLine(new string('w', 900000000));   //OLE (Output Limit Exceeded)  出力多すぎ
            }

        }

        var mle1 = new List<long>(10000000);
        var mle2 = new long[10000000, 10000000];


        Console.WriteLine($"{crest[0]} {crest[1]} {crest[2]}");

    } // Main
}     // Class