在两个级别输入有效值之前，如何继续请求输入？

Question

我正在做一个问题，其中我为拼字游戏创建了各种功能。首先，我想让用户输入n或r或e开始新游戏/重放最后一手牌/结束游戏。

一旦游戏开始，我想让用户输入u或c来让用户或计算机玩。

我陷入了问题的最后一部分。

我的代码：

hand = None
while True:
    choice = input('Enter n to deal a new hand, r to replay the last hand, or e to end game: ').lower()
    if choice == 'e':
        break
    
    elif choice=='n':
        Your_choice = input('Enter u to play yourself or c to let the computer play: ')
        
        if Your_choice == 'u':
                hand = dealHand(HAND_SIZE)
                playHand(hand, wordList, HAND_SIZE)
        elif Your_choice == 'c':
                hand = dealHand(HAND_SIZE)
                compPlayHand(hand, wordList,HAND_SIZE)
        else:
                print('Invalid command.')
                
    elif choice == 'r':
        if hand == None:
            print('You have not played a hand yet. Please play a new hand first!')
        else:
            Your_choice = input('Enter u to play yourself or c to let the computer play: ')
            
            if Your_choice == 'u':
                if hand != None:
                    playHand(hand.copy(), wordList, HAND_SIZE)
                else:
                    print('You have not played a hand yet. Please play a new hand first!')
            elif Your_choice == 'c':
                if hand != None:
                    compPlayHand(hand.copy(), wordList, HAND_SIZE)
                else:
                    print('You have not played a hand yet. Please play a new hand first!')
            else:
                print('Invalid command.')
    else:
            print('Invalid command.')

如果内部循环的选择不是u或c，它应该反复通知并询问，直到u或c是输入。但它是在初审后从那个循环中出来的。

理想输出：

Enter n to deal a new hand, r to replay the last hand, or e to end game: n
Enter u to have yourself play, c to have the computer play: x
Invalid command.

Enter u to have yourself play, c to have the computer play: y
Invalid command.

Enter u to have yourself play, c to have the computer play: z
Invalid command.

Enter u to have yourself play, c to have the computer play: k
Invalid command.

我的输出：

Enter n to deal a new hand, r to replay the last hand, or e to end game: n

Enter u to play yourself or c to let the computer play: x

Invalid command.

Enter n to deal a new hand, r to replay the last hand, or e to end game: y

Invalid command.

问题是，当用户在第二级输入无效命令时，我的代码开始询问第一级的问题。

Answer 1

您需要的是python中的break语句，它停止最内部的循环，您可以使用该语句执行以下操作：

while:
    Your_choice = input('Enter u to play yourself or c to let the computer play: ')
    if Your_choice in ["u", "c"]:
        # Do stuff
        break
    else:
        print("Incorrect option")

文档中的更多信息：https://docs.python.org/3/tutorial/controlflow.html#break-and-continue-statements-and-else-clauses-on-loops