Problem:
Score : 100 points

Problem Statement

Two deer, AtCoDeer and TopCoDeer, are playing a game called Honest or Dishonest.
In this game, an honest player always tells the truth, and an dishonest player always tell lies.
You are given two characters a and b as the input. Each of them is either H or D, and carries the following information:

If a=H, AtCoDeer is honest; if a=D, AtCoDeer is dishonest.
If b=H, AtCoDeer is saying that TopCoDeer is honest; if b=D, AtCoDeer is saying that TopCoDeer is dishonest.

Given this information, determine whether TopCoDeer is honest.

Constraints

a=H or a=D.

b=H or b=D.

Input

The input is given from Standard Input in the following format:

a b

Output

If TopCoDeer is honest, print H. If he is dishonest, print D.

Sample Input 1

H H

Sample Output 1

H

In this input, AtCoDeer is honest. Hence, as he says, TopCoDeer is honest.

Sample Input 2

D H

Sample Output 2

D

In this input, AtCoDeer is dishonest. Hence, contrary to what he says, TopCoDeer is dishonest.

Sample Input 3

D D

Sample Output 3

H

Solution in C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApplication2
{
    class Program
    {
        static void Main(string[] args)
        {
            //int N = int.Parse(Console.ReadLine());

            string[] tmp = Console.ReadLine().Split(' ');

            string a = tmp[0];
            string b = tmp[1];

            if(a == "H")
            {
                if(b == "H")
                {
                    Console.WriteLine("H");
                }
                else
                {
                    Console.WriteLine("D");
                }
            }
            else
            {
                if (b == "H") Console.WriteLine("D");
                else Console.WriteLine("H");
            }

            //int[] hogeArray = new int[N];
            //for(int i = 0;i<N;i++)
            //{
            //    hogeArray[i] = int.Parse(tmp[i]);
            //}
        }
    }
}