#密码输入检测 密码长度不少于8个字符，而且必须包含大写/小写/数字

import re

def inputPasswordCheck(strInput):

    strInput = input()

    #长度判断

    if len(strInput) != 8:

        print('len error')

        return

    #表达式匹配 小写字母

    PasswordCheck = re.compile(r'[a-z]')

    mo = PasswordCheck.search(strInput)

    if mo == None:

        print('search a-z error')

        return

    #表达式匹配 数字

    PasswordCheck = re.compile(r'[0-9]')

    mo = PasswordCheck.search(strInput)

    if mo == None:

        print('search 1-9 error')

        return

    #表达式匹配 大写字母

    PasswordCheck = re.compile(r'[A-Z]')

    mo = PasswordCheck.search(strInput)

    if mo == None:

        print('search A-Z error')

        return

    return strInput

if __name__== '__main__':

    strInput = ''

    i = 0

    print('please input a password:')

    try:

        while True:

            reGet = inputPasswordCheck(strInput)

            i = i+1

            #如果输入成功则打印

            if reGet != None:

                print(reGet)

            #如果输入次数大于5次退出

            if i >5 :

                print('try time enouth the demo exit')

                break

    except KeyboardInterrupt:

        print('the demo exit')