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++14 (GCC 5.4.1) (judge verdict: Accepted)

#include<iostream>
#include<algorithm>
#include<vector>
#include<string>
using namespace std;
int main(){
 char b;
 cin >> b;
 if (b == 'A'){
   cout << "T\n";
 }
 if (b == 'T'){
   cout << "A\n";
 }
   if (b == 'C'){
   cout << "G\n";
 }
 if (b == 'G'){
   cout << "C\n";
 }
  return 0; 
}