Problem:
Score : 100 points

Problem Statement

On the Planet AtCoder, there are four types of bases: A, C, G and T. A bonds with T, and C bonds with G.

You are given a letter b as input, which is A, C, G or T. Write a program that prints the letter representing the base that bonds with the base b.

Constraints

b is one of the letters A, C, G and T.

Input

Input is given from Standard Input in the following format:

b

Output

Print the letter representing the base that bonds with the base b.

Sample Input 1

A

Sample Output 1

T

Sample Input 2

G

Sample Output 2

C

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

using System;
using System.Collections.Generic;

namespace AtCoder {

    class Program {


        static void Main(string[] args) {

            var temp = Console.ReadLine();

            var map = new Dictionary<string, string>() {
                { "A", "T" },
                { "C", "G" },
                { "T", "A" },
                { "G", "C" }
            };

            Console.WriteLine(map[temp]);
        }
    }
}