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)

/*      Abhijith    */
#include<bits/stdc++.h>
#include<iomanip>
#define lld long long int
#define ld long double
#define mod 1000000007
#define all(v) v.begin(),v.end()
#define rep(i,a,b)	for(lld i=a;i<=b;i++)
#define repr(i,a,b) for(lld i=a;i>=b;i--)
#define pb push_back
#define mp make_pair
using namespace std;
int main()
{
     ios_base::sync_with_stdio(false);
     cin.tie(0);
     cout.tie(0);
     char s;
     cin>>s;
     if(s=='A')
     {
         cout<<"T"<<endl;
     }
     else if(s=='T')
     {
         cout<<"A"<<endl;
     }
     else if(s=='C')
     {
         cout<<"G"<<endl;
     }
     else if(s=='G')
     {
         cout<<"C"<<endl;
     }
    return 0;
}