如何使用随机选择的函数作为 if 语句中的条件？

Question

首先我想说的是，我在 Python 方面处于非常初级的水平，可能还没有以最有效的方式使用它进行编码。

我正在尝试构建一个程序，为用户提供简单的数学测验。它随机选择一个问题（加法、减法、除法或乘法）并要求用户输入以回答问题。

如果用户答对了，我要祝贺他们。如果他们答错了，我想给他们正确的答案。我为我想给用户的每种不同类型的问题制作了函数，并将它们添加到列表中。然后我随机选择了一个函数来调用并提供给用户。

从这里开始，我想我只需将一个变量 (prob) 分配给随机选择的函数，并将其用作一系列 if else 语句中的条件。这是行不通的。相反，它会跳过我希望它发回给他们的消息，然后直接转到我的下一个 input 命令。我猜这是因为我不能真正为随机选择函数分配一个变量。

我还能如何编写代码以使其执行我希望它执行的操作？

import random

def problem():
  global add
  def add():
    num1 = random.randint(0, 999)
    num2 = random.randint(0, 999)
    global addition
    addition = num1 + num2
    op1 = f' {num1}\n+{num2}'
    print(op1)
  global sub
  def sub():
    num1 = random.randint(0, 999)
    num2 = random.randint(0, 999)
    global subtract
    subtract = num1 - num2
    op2 = f' {num1}\n-{num2}'
    if subtract < 0:
      sub()
    elif subtract > 0:
      print(op2)
  global mult
  def mult():
    num1 = random.randint(1, 12)
    num2 = random.randint(1, 12)
    global multiply
    multiply = num1 * num2
    op3 = f'{num1} * {num2}'
    print(op3)
  global div
  def div():
    num1 = random.randint(0, 150)
    num2 = random.randint(0, 150)
    global divide
    divide = num1 / num2
    op4 = f'{num1} / {num2}'
    if num1 % num2 == 0:
      print(op4)
    elif num1 % num2 != 0 or num2 == 0:
      div()
  global numlist
  numlist = [add, sub, mult, div]
  prob = random.choice(numlist)()
  answer = input()
  if prob == numlist[0] and answer == f'{add.addition}':
    print(f'Congrats! You got it right.')
  elif prob == numlist[0] and answer != f'{add.addition}':
    print(f'Incorrect. The answer is {add.addition}.')
  elif prob == numlist[1] and answer == f'{sub.subtract}':
    print(f'Congrats! You got it right.')
  elif prob == numlist[1] and answer != f'{sub.subtract}':
    print(f'Incorrect. The answer is {sub.subtract}.')
  elif prob == numlist[2] and answer == f'{mult.multiply}':
    print(f'Congrats! You got it right.')
  elif prob == numlist[2] and answer != f'{mult.multiply}':
    print(f'Incorrect. The answer is {mult.multiply}.')
  elif prob == numlist[3] and answer == f'{div.divide}':
    print(f'Congrats! You got it right.')
  elif prob == numlist[3] and answer != f'{div.divide}':
    print(f'Incorrect. The answer is {div.divide}.')
  done = input('Type "done" if you want to be done. Press Enter if you want another problem.\n')
  while done == '':
    problem()
    if done == 'done' or done == 'Done':
      break

problem()

Answer 1

您可以通过将 prob 替换为包含由 randrange 函数生成的随机数的变量来实现。此外，您的代码中有几个错误，例如 add.addition ，这没有任何意义，因为函数不能具有任何属性。我将其更改为简单的 addition 以修复所有编译器错误，因此最终代码如下所示：

import random

def problem():
  global add
  def add():
    num1 = random.randint(0, 999)
    num2 = random.randint(0, 999)
    global addition
    addition = num1 + num2
    op1 = f' {num1}\n+{num2}'
    print(op1)
  global sub
  def sub():
    num1 = random.randint(0, 999)
    num2 = random.randint(0, 999)
    global subtract
    subtract = num1 - num2
    op2 = f' {num1}\n-{num2}'
    if subtract < 0:
      sub()
    elif subtract > 0:
      print(op2)
  global mult
  def mult():
    num1 = random.randint(1, 12)
    num2 = random.randint(1, 12)
    global multiply
    multiply = num1 * num2
    op3 = f'{num1} * {num2}'
    print(op3)
  global div
  def div():
    num1 = random.randint(0, 150)
    num2 = random.randint(0, 150)
    global divide
    divide = num1 / num2
    op4 = f'{num1} / {num2}'
    if num1 % num2 == 0:
      print(op4)
    elif num1 % num2 != 0 or num2 == 0:
      div()
  global numlist
  numlist = [add, sub, mult, div]
  num = random.randrange(4)
  prob = numlist[num]()
  answer = input()
  if num == 0 and answer == f'{addition}':
    print(f'Congrats! You got it right.')
  elif num == 0 and answer != f'{addition}':
    print(f'Incorrect. The answer is {addition}.')
  elif num == 1 and answer == f'{subtract}':
    print(f'Congrats! You got it right.')
  elif num == 1 and answer != f'{subtract}':
    print(f'Incorrect. The answer is {subtract}.')
  elif num == 2 and answer == f'{multiply}':
    print(f'Congrats! You got it right.')
  elif num == 2 and answer != f'{multiply}':
    print(f'Incorrect. The answer is {multiply}.')
  elif num == 3 and answer == f'{divide}':
    print(f'Congrats! You got it right.')
  elif num == 3 and answer != f'{divide}':
    print(f'Incorrect. The answer is {divide}.')
  done = input('Type "done" if you want to be done. Press Enter if you want another problem.\n')
  while done == '':
    problem()
    if done == 'done' or done == 'Done':
      break

problem()

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