用戶登錄程序

# __author__ = Leo li
# !/usr/bin/env python
# -*- coding:utf-8 -*-
a = open("username.txt","r+")
x = open("password.txt","r+")
y = x.readlines()
b = a.readlines()
f = open("msg.txt","r+")
m = f.readlines()
counter = 0
cmd = 0
ax = 0
while cmd < 1:
    a = open("username.txt","r+")
    x = open("password.txt","r+")
    y = x.readlines()
    b = a.readlines()
    print("歡迎來到Python論壇登陸界面")
    print("1.註冊用戶")
    print("2.登錄用戶")
    print("3.退出")
    chose = input("請輸入你的選項：")
    if chose == '1':
        while chose:
            user = input("請輸入您要註冊的用戶名:")
            if user+"\n" in b:
                print("該用戶名已存在，請重新輸入")
            else:
                pwd = input("請輸入您的密碼：")
                c = open("password.txt","a+")
                c.write(pwd+"\n")
                a = open("username.txt","a+")
                a.write(user+"\n")
                p = open("msg.txt","a+")
                p.write("True\n")
                p.close()
                c.close()
                a.close()
                x.close()
                print("註冊成功！請重新運行登錄程序！")
                exit()
    elif chose == '2':
        while chose:
            username = input("請輸入您的用戶名：")
            password = input("請輸入您的密碼：")
            d = open("username.txt",'r+')
            if username+"\n" not in d:
                print("您輸入的用戶名不存在，請重新輸入")
                d.close()


            else:
                q = open("msg.txt",'r+')
                w = q.readlines()
                e = b.index(username+"\n")
                if w[e] == "True\n":

                        if counter <2:
                            if password+"\n" == y[e]:
                                print("登錄成功！歡迎進入")
                                exit()

                            else:
                                print("你的密碼錯誤，請重新輸入")
                                counter+=1
                                continue
                        else:
                            g = open("msg.txt","w+")
                            m[e] = "False\n"
                            g.writelines(m)
                            g.close()
                            print("由於你嘗試太多次，系統已鎖定此賬戶，請聯繫管理員後重試")
                            print("正在退出程序…………")
                            exit()

                else:
                    print("您好，由於你的密碼輸入錯誤次數過多，系統已鎖定此賬戶，請聯繫管理員後重試")
                    print("正在返回登錄界面……")
                    print("\n")
                    break


    elif chose == '3':
        print("正在退出……")
        exit()
    else:
        print("您的輸入有誤，請輸入您要選擇的序號（“1”，“2”，“3”）")