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 b;
  scanf("%c", &b);

  if(b == 'A') {
    printf("T\n");
  } else if(b == 'C') {
    printf("G\n");
  } else if(b == 'G') {
    printf("C\n");
  } else if(b == 'T') {
    printf("A\n");
  }
  return 0;
}