如何使用用户输入打破无限循环

Question

我对 Python 很陌生。

我制作了一个数学程序，每次你做对最后一道题时，它都会不断生成一个新的数学题。但是我不知道如何退出/中断 while True 循环并从加法切换到减法。

import random

while True:

    question = input("press 1 for addition, press 2 for subtraction.")
    if question == "1":
        print("Try your skill at these problems.")
        number1 = random.randint(0, 9)
        number2 = random.randint(0, 9)

        while True:
            print(number1, "+", number2, "=")
            number3 = number1+number2
            answer = int(input())
            if answer == number3:
                print("Great Job, Try this one.")
                number1 = random.randint(0, 9)
                number2 = random.randint(0, 9)
            else:
                print("Have another go")
            #I want to push space to break this while loop
            #and be able to switch to subtraction problems    
    if question == "2":
        print("Try your skill at these problems.")
        number1 = random.randint(0, 9)
        number2 = random.randint(0, 9)

        while True:
            print(number1, "-", number2, "=")
            number3 = number1-number2
            answer = int(input())
            if answer == number3:
                print("Great Job, Try this one.")
                number1 = random.randint(0, 9)
                number2 = random.randint(0, 9)
            else:
                print("Have another go")
            #I want to push space to break this while loop
            #and be able to switch to addition problems

如何指定用户输入（例如空格键）来阻止 while True: 循环。我查看了针对类似问题发布的其他答案，但是当我尝试它们时，它们都会阻止我的代码产生超过一定数量的问题。

有没有办法做到这一点。还是我需要找到一种方法来运行这个数学游戏而无需 while True 循环？

Answer 1

在无法确定循环次数时使用while循环很好，使用while循环的方法做得很好。

如果你想退出while循环，你可以尝试在while循环之外定义一个变量（条件变量），并设置变量成为你的while条件。要退出循环，只需更改条件变量的值即可。

代码示例：

import random

while True:

    conditions = True # my changes
    question = input("press 1 for addition, press 2 for subtraction.")
    if question == "1":
        print("Try your skill at these problems.")
        number1 = random.randint(0, 9)
        number2 = random.randint(0, 9)

        while conditions: # my changes
            print(number1, "+", number2, "=")
            number3 = number1+number2
            answer = int(input())
            if answer == number3:
                print("Great Job, Try this one.")
                number1 = random.randint(0, 9)
                number2 = random.randint(0, 9)
                checking = input("Another round? (Y/N)") # my changes
                if checking == "N": # my changes
                    conditions = False # my changes
            else:
                print("Have another go")
    if question == "2":
        print("Try your skill at these problems.")
        number1 = random.randint(0, 9)
        number2 = random.randint(0, 9)

        while conditions: # my changes
            print(number1, "-", number2, "=")
            number3 = number1-number2
            answer = int(input())
            if answer == number3:
                print("Great Job, Try this one.")
                number1 = random.randint(0, 9)
                number2 = random.randint(0, 9)
                checking = input("Another round? (Y/N)") # my changes
                if checking == "N": # my changes
                    conditions = False # my changes
            else:
                print("Have another go")