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 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <stdio.h>
#include<string.h>

int main(void) {
  char S[11];
  int i, ans = 0, cnt = 0;
  scanf("%c", S);
  
  for( i = 0; i < 11; i++ ) {
    if( S[i]=='A' || S[i]=='C' || S[i]=='G' || S[i]=='T' )
    cnt++;
    else if( ans < cnt ) {
      ans=cnt; cnt=0;
    }
  }
  printf("%d\n", ans);
  return 0;
}