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: Wrong Answer)

#include <stdio.h>
int main(void) {
  char b;
  char x;
  scanf("%c",&b);
  if (b == "A") {
    x = "T";
    printf("%c",x);
  }else if (b == "T") {
    x = "A";
    printf("%c",x);
  }else if (b == "C") {
    x = "G";
    printf("%c",x);
  }else if (b == "G") {
    x = "C";
    printf("%c",x);
  }
  return 0;
}