注册小程序

# ### 注册
# (1)检测两次密码如果相同,确认注册成功
# (2)检测两次密码如果不同,提示两次密码不一致
# (3)用户名不能重复

accountlist = []
fp = open("user.txt",mode="r+",encoding="utf-8")
for i in fp:
    account = i.split(":")[0]
    accountlist.append(account)
sign = True
while sign:
    name = input("请输入注册用户名:")
    if name == "" or " " in name:
        print("抱歉,用户名中有非法字符,请重新输入")
    else:
        if name in accountlist:
            print("抱歉,用户名已经存在")
        else:
            pw1 = input("请输入注册密码:")
            while True:
                pw2 = input("请再次输入注册密码:")
                if pw1 == pw2:
                    strvar = name + ":" + pw2 + "\n"
                    fp.write(strvar)
                    fp.close()
                    sign = False
                    print("恭喜,你已注册成功!")
                    break
                elif pw2.upper() == "Q":
                    print("欢迎下次再来!")
                    break
                else:
                    print("两次密码不一致,请重新输入")