题解 | 牛牛的考试

T = eval(input())
for i in range(T):
    A = input()
    B = input()
    C = input()
    D = input()
    options = ['A','B','C','D']
    length = [len(A),len(B),len(C),len(D)]
    min_len = min(length)
    count_min = sum(1 for l in length if l == min_len)
    max_len = max(length)
    count_max = sum(1 for l in length if l == max_len)
    if count_min == 1 and count_max != 1:
        for i in range(4):
            if length[i] == min_len:
                print(options[i])
    elif count_max == 1 and count_min !=1 :
        for i in range(4):
            if length[i] == max_len:
                print(options[i])
    else :
        print('C')