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 Haskell (GHC 7.10.3) (judge verdict: Accepted)

main=getLine>>=putStr.solve
solve c
  | c=="A" = "T"
  | c=="T" = "A"
  | c=="C" = "G"
  | c=="G" = "C"