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: Accepted)

using System;

namespace ConsoleApp2
{
    class Program
    {
        static void Main(string[] args)
        {
            var num = int.Parse(Console.ReadLine());

            if (num == 1)
            {
                Console.WriteLine("Hello World");
            }
            else if (num == 2)
            {
                int sum = 0;

                for(int i = 0; i < 2; i++)
                {
                    var num2 = int.Parse(Console.ReadLine());
                    sum += num2;
                }

                Console.WriteLine(sum);
                    
            }

            #if DEBUG
                Console.WriteLine("続行するには何かキーを押してください．．．");
                Console.ReadKey();
            #endif
        }
    }
}