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(int argc, char const *argv[]) {
  char B;
  scanf("%c", &B);
  if (B=='A') {printf("T");}
  if (B=='T') {printf("A");}
  if (B=='C') {printf("G");}
  if (B=='G') {printf("C");}
  return 0;
}