二分搜索游戏

Question

我开始学习Python，并试图优化这个二分法搜索游戏。

high = 100
low = 0
guess = (high + low)/2  


print('Please think of a number between 0 and 100!')

guessing = True
while guessing:
    print('Is your secret number ' + str(guess) + '?')
    pointer = raw_input("Enter 'h' to indicate the guess is too high. Enter 'l'   to   indicate the guess is too low. Enter 'c' to indicate I guessed correctly.")
    if pointer == 'h':
        high = guess
        guess = (low + guess)/2

    elif pointer == 'l':
        low = guess
        guess = (high + guess)/2

    elif pointer == 'c':
        guessing = False

    else:
        print('Sorry, I did not understand your input.')
print('Game over. Your secret number was: ' + str(guess))

Answer 1

我认为有些东西会改进您的代码，这是非常正确的：

• 有了high和low的变量，就不应该在开头的print中硬编码它们的值。
• 您应该使用//来确保得到整数除法。
• 如果将guess = (low + high) // 2作为while循环中的第一行，则只能编写一次。
• 在检查pointer时，您可能希望首先将其转换为小写，以确保h和H都被理解。
• 使您的代码在最大行长等方面符合PEP8。
• 使用format方法的str可以更清楚地显示您正在打印的内容。

把这一切结合在一起：

high, low = 100, 0

print('Please think of a number between {0} and {1}!'.format(low, high))

guessing = True
while guessing:
    guess = (low + high) // 2
    print('Is your secret number {0}?'.format(guess))
    pointer = raw_input("Enter 'h' to indicate the guess is too high. "
                        "Enter 'l' to indicate the guess is too low. "
                        "Enter 'c' to indicate I guessed correctly.").lower()
    if pointer == 'h' :
        high = guess
    elif pointer == 'l' :
        low = guess
    elif pointer == 'c':
        guessing = False
    else:
        print('Sorry, I did not understand your input.')

print('Game over. Your secret number was {0}.'.format(guess))

Answer 2

除了Jaime的观点。

1. 去掉guessing标志，只需有一个带有break语句的无限循环。
2. pointer是该变量的一个非常通用的名称，特别是因为它在其他编程语言中意味着其他一些东西。

Answer 3

在完成杰米的答复后，请注意：

键入'c'时，即使数字不是您所想的，始终打印代码print('Game over. Your secret number was {0}.'的这一部分。

因此，为了避免这种情况，还必须在(str(numbers) == str(guess))的分支上测试(response == 'c')：

high, low = 100, 0
guess = (low + high) // 2

numbers = raw_input('Please think of a number between {0} and {1}!'.format(low, high))

guessing = True
while guessing:

    print('Is your secret number {0}?'.format(guess))
    response = raw_input("Enter 'h' to indicate the guess is too high. "
                        "Enter 'l' to indicate the guess is too low. "
                        "Enter 'c' to indicate I guessed correctly.").lower()
    if response == 'h' :
        high = guess
    elif response == 'l' :
        low = guess
    elif (response == 'c') and (str(numbers) ==  str(guess)) :       
            print('Game over. Your secret number was {0}.'.format(guess))
            break
    else:
        print('Sorry, I did not understand your input.')
    guess = (low + high) // 2