作為一個迷惘的金融狗，曾關注一些實習要求python，開始瞭解這門語言。

後來發現在金融這一領域的實習要求中，要求python而不是各種證書&實習經歷的僅僅是佔少數。

這條路，漫漫長而又艱險。一定會遇見光，但是很可能不是屬於金融背景的python程式設計師。也許是IT、數理背景出身的具備python程式設計能力的懂得基礎金融知識的人吧。

金融金融，當今也許皇冠不在，但是仍是不錯的選擇。

程式設計師之路

只求不脫髮&性別不歧視。

若是個男生倒不介意了

——————以下為主要內容——————

本次程式碼實現的是 註冊、登陸以及刪除賬戶的功能。

如果有更簡潔、高效的寫法，歡迎和我交流呀～

# Author:王帥帥的升級打怪之路
'''
登陸介面可實現功能：
註冊（可檢測是否重名）；
登陸（輸錯三次鎖定）；
登出賬戶（輸錯三次鎖定）。
可實現註冊後接著登陸或者登出賬戶。
'''

# 儲存使用者名稱和密碼的列表。
usernameANDpassword_list = [["mac", "abc123"], ["apple", "6789bnm"], ["pencil", "123456"]]

UserChoice = input("Enter register, login or delete.")
Judgement = True
 
while Judgement:
    if UserChoice == "register":
        flag1 = True
        while flag1:
            username = input("Register:input a username.")
            keyV = 0  # 用於判斷註冊輸入的使用者名稱是否已存在。
            for i in usernameANDpassword_list:
                if username == i[0]:
                    keyV 
 
+= 1
                else:
                    keyV += 0
            if keyV != 0:
                print("The name already exists, please try another one.")
            else:
                password = input("Register:input your password.")
                usernameANDpassword_list.append([username, password])
                print("you've already registered.")
                flag1 = False  # 註冊成功之後跳出while迴圈
                Continue = input("Please input N to exist or Y to continue other operations.")
                if Continue == "N":
                    Judgement = False
                else:
                    UserChoice = input("Enter register, login or delete.")

    elif UserChoice == "login":
            count = 0
            keyV = 0
            while count < 3:
                username = input("Login:input your username.")
                password = input("Login:input your password.")
                for i in usernameANDpassword_list:
                    if username == i[0] and password == i[1]:
                        keyV += 1
                    else:
                        keyV += 0
                if keyV != 0:
                    print("you've login!!!")
                    Continue = input("Please input N to exist or Y to continue login or delete.")
                    if Continue == "N":
                        Judgement = False
                    else:
                        UserChoice = input("Enter register, login or delete.")
                    break  # 退出while迴圈
                else:
                    print("your username or password is wrong.")
                    count += 1
                if count == 3:
                    print("you've tried too many times.Your account has been locked.")
                    Judgement = False
    elif UserChoice == "delete":
        count = 0
        keyV = 0
        while count < 3:
            username = input("Delete:input your username.")
            password = input("Delete:input your password.")
            for i in usernameANDpassword_list:
                if username == i[0] and password == i[1]:
                    keyV += 1
                else:
                    keyV += 0
            if keyV != 0:
                delete_confirm = input("Are you sure? \
                Please input Y to delete or N to cancel.")
                if delete_confirm == "Y":
                    index = usernameANDpassword_list.index([username, password])
                    del usernameANDpassword_list[index]
                    print("your account has been deleted.")
                    Continue = input("Please input N to exist or Y to continue login or delete.")
                    if Continue == "N":
                        Judgement = False
                    else:
                        UserChoice = input("Enter register, login or delete.")
                    break
                    # usernameANDpassword_list.pop(index) 另一種刪除方法。
                else:
                    print("you cancel this operation.")
                    Continue = input("Please input N to exist or Y to continue login or delete.")
                    if Continue == "N":
                        Judgement = False
                    else:
                        UserChoice = input("Enter register, login or delete.")
                    break
            else:
                count += 1
            if count == 3:
                print("you've tried too many times.")
                Continue = input("Please input N to exist or Y to continue login or delete.")
                if Continue == "N":
                    Judgement = False
                else:
                    UserChoice = input("Enter register, login or delete.")
            else:
                print("the username or password is wrong or unavailable.")

    else:
        print("you didn't correctly choose a function.")
        Judgement = False