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 JavaScript (node.js v5.12) (judge verdict: Accepted)

function Main(input) {
    var mozi = input[0];
    
    var result = '';
    if (mozi === 'A') {
        result = 'T';
    } else if (mozi === 'T') {
        result = 'A';
    } else if (mozi === 'C') {
        result = 'G';
    } else if (mozi === 'G') {
        result = 'C';
    }
    console.log(result);
}
 
Main(require("fs").readFileSync("/dev/stdin", "utf8").trim().split(/\n|\s/));