题解 | #密码验证合格程序#

def check_passwd(passwd: str) -> bool:
    # 1. 校验密码长度
    if len(passwd) <= 8:
        return False
    
    # 2. 校验字符
    num = [0] * 4
    for char in passwd:
        if char.isupper():
            num[0] = 1
        elif char.islower():
            num[1] = 1
        elif char.isdigit():
            num[2] = 1
        else:
            num[3] = 1
    if sum(num) < 3:
        return False
                 
    # 3. 重复子串
    # 隐含条件是判断是否存在长度为3的子串
    li = []
    for i in range(len(passwd) - 2):
        li.append(passwd[i:i+3])
    if len(set(li)) == len(li):
        return True
    else:
        return False


while True:
    try:
        print('OK' if check_passwd(input()) else 'NG')
    except:
        break