python - 猜测 1 到 100 之间的数字

Question

这个问题已经有答案了:

Guessing algorithm does not seem to work, guessing number by Python (3 个回答)

已关闭 5 年前。

程序应该从用户那里获取一个整数，并使用二分搜索来猜测该整数是什么。

user_num = (int(input("Please think of a number between 0 and 100! ")))
low = 0
high = 100
ans = (high + low)//2

while True:
    print("is your secret number " + str(ans))
    check_ans = input("""enter 'h' to indicate if the guess is too high. 
    enter 'l' to indicate if the guess is too low. 
    enter 'c' if I guessed correctly.""")

      if check_ans == 'h':
        high = ans//2
        ans = high

      elif check_ans == 'l':
        low = ans*2
        ans = low

      elif check_ans == 'c' and check_ans == user_num:
        print("Game over. Your secret number was: " + str(ans))
        break

      else:
        print("I do not understand your command")

我相信我遇到的问题发生在 while 循环中。我需要程序知道一旦达到阈值就何时停止。假设我的整数是 34，一旦我点击“h”作为输入，它就会下降到 25。现在如果我点击“l”，它就会跳回 50。

我想我的问题是如何更新 ans 变量以便程序知道保持在该范围内？

Answer 1

我们来看看你的条件。我们想要做的是根据程序收到的答案重新定义 low 和 high。

if check_ans == 'h':
    # We know that ans is lower, so we set our higher bound to slightly below ans
    high = ans - 1

elif check_ans == 'l':
    # We know that ans is higher, so we set our lower bound to slightly above ans
    low = ans + 1

然后在循环开始时，您希望通过执行 ans = (high + low)//2 来根据间隔获取 ans。

总的来说，这给出了

user_num = (int(input("Please think of a number between 0 and 100! ")))

low = 0
high = 100

while True:
    ans = (high + low)//2

    print("is your secret number " + str(ans))
    check_ans = input("""
    enter 'h' to indicate if the guess is too high. 
    enter 'l' to indicate if the guess is too low. 
    enter 'c' if I guessed correctly.""")

    if check_ans == 'h':
      high = ans - 1

    elif check_ans == 'l':
      low = ans + 1

    elif check_ans == 'c' and check_ans == user_num:
      print("Game over. Your secret number was: " + str(ans))
      break

    else:
      print("I do not understand your command")