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-----
A

-----Sample Output-----
T

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