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: Runtime Error)

#include<stdio.h>
int main(){

	char a,b;

	scanf("%s", &a);

	if(a=='A'){
		b = 'T';
	}

	if(a=='T'){
		b = 'A';
	}
	if(a=='G'){
		b = 'C';
	}
	if(a=='C'){
		b = 'G';
	}
	

	printf("%s\n",b);

}