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 <bits/stdc++.h>
#define rep(i,n) for (int i = 0; i < (n); ++i)
const int INF = 2147483647;//int max
const int MOD = 1000000007;
using namespace std;
using ll = long long;
using P = pair<int,int>;


int main() {
    char c;
    cin >> c;
    if(c == 'A')printf("T\n");
    else if(c == 'T')printf("A\n");
    else if(c == 'G')printf("C\n");
    else printf("G\n");
    return 0;
}

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