#AT1321. A - Double Helix

A - Double Helix

A - Double Helix

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:

bb

Output

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


A
T

G
C