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 Python (3.4.3) (judge verdict: Runtime Error)

from itertools import accumulate
n, q = list(map(int, input().split()))
s = input()
a = [list(map(int, input().split())) for i in range(q)]

flg = []

for i in range(n-1):
    tmp = s[i:i+2]
    if tmp == 'AC':
        flg.append(1)
    else:
        flg.append(0)
    
flg2 = [0] + flg
flg2 = list(accumulate(flg2))

for l in a:
    print(flg2[l[1]-1] - flg2[l[0]-1])