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 (GCC 5.4.1) (judge verdict: Accepted)

#include<stdio.h>

int main(void) {
	char in;
	char out;

	scanf("%c", &in);
	switch (in) {
	case 'A':
		out = 'T';
		break;
	case 'T':
		out = 'A';
		break;
	case'G':
		out = 'C';
		break;
	case'C':
		out = 'G';
		break;
	}
	printf("%c\n", out);
	return 0;

}