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 Scala (2.11.7) (judge verdict: Runtime Error)

class Main {
  def main(args: Array[String]): Unit = {
    val out = io.StdIn.readLine.map {
      _.toString count {
          Set('A', 'C', 'G', 'T').contains(_)
        }
    }
    println(out.head)
  }
}