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 Kotlin (1.3.71) (judge verdict: Accepted)

fun solve(S: String) {
    var ans = ""
    if (S == "A") {
        ans = "T"
    } else if (S == "T") {
        ans = "A"
    } else if (S == "C") {
        ans = "G"
    } else if (S == "G") {
        ans = "C"
    }
    println(ans)
}

fun main() {
    val S = readLine()!!
//    val N = readLine()!!.toInt()
//    val (N, M) = readLine()!!.split(" ").map { it.toInt() }
//    val A = readLine()!!.split(" ").map { it.toInt() }
    solve(S)
}