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 <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

#define REP(i, n) for (int i = 0; i < (int)(n); i++)
#define FOR(i, a, b) for (int i = (int)(a); i < (int)(b); i++)
#define FORR(i, a, b) for (int i = (int)(b)-1; i >= (int)(a); i--)

#define CHMIN(a, b) (a) = min((a), (b))
#define CHMAX(a, b) (a) = max((a), (b))

#define DEBUG(x) cout << #x << ": " << (x) << endl
#define PRINT(x) cout << x << endl
int main() {
  int N;
  cin >> N;

  int A, B;

  if (N == 2) {
    cin >> A >> B;
    PRINT(A + B);
  } else {
    PRINT("Hello World");
  }
}