import random

ALP = ['A', 'B', 'C', 'D', 'E', 'F', 'G']
r = random.choice(ALP)
alp = ''

for i in ALP:
    if i != r:
        alp = alp + i
        
print(alp)
ans = input('缺少哪個字母呢?')

if ans == r:
    print('答案正確')
else:
    print('答案錯誤')