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>
#define N 100017
int ACjudge(int,int,char*);
int main(void){
  int n,Q,l,r;
  char S[N];
  scanf("%d %d",&n,&Q);
  scanf("%s",S);
  for(int i=0;i<Q;i++){
    scanf("%d %d",&l,&r);
    if(r<=n){
    	int j=ACjudge(l,r,&S[0]);
    	printf("%d\n",j);
  	}
  }
  return 0;
}
int ACjudge(int x,int y,char *z){
  z += x-1;
  int t=0;
  for(int k=0;k<y-x;k++){
    if(*z=='A' && *(z+1)=='C'){
      t++;
    }
    z++;
  }
  return t;
}