反向猜数游戏 Python

Question

So, recently i have been trying to program a reverse number guessing game whereby the computer tries to guess the number i have in mind. The output i should get is as shown below:

Enter the range: 6
Think of a random number between 1 and 6 and press enter once done!
Is it smaller than 4, 'y' or 'n'?y
Is it smaller than 2, 'y' or 'n'?n
Is it smaller than 3, 'y' or 'n'?y
Wonderful it took me 3 questions to find out that you had the number 2 in mind!

These are my codes so far:

import random

maxNum = int(input('Enter the range: '))
input('Think of a random number between 1 and ' + str(maxNum) + ' and press enter once done!')
lowBound = 1
highBound = maxNum
response = ''
noOfGuesses = 0
numberHasBeenGuessed = False
randomNumber = random.randint(lowBound,highBound)

while not numberHasBeenGuessed:
    noOfGuesses += 1
    response = input("Is it smaller than " + str(randomNumber) + ", 'y' or 'n'?")
    if response == "n" or response == 'N':
        lowBound = randomNumber + 1   
        randomNumber = random.randint(lowBound,highBound)
    elif response == "y" or response == "Y":
        highBound = randomNumber - 1
        randomNumber = random.randint(lowBound,highBound)
    else:
        print ('Please only type y, Y, n or N as responses')
        
numberHasBeenGuessed = True        
print('Wonderful it took me ' + str(noOfGuesses) + ' attempts to guess that you had the number ' + str(randomNumber) + ' in mind')

The main algorithm is working but somehow it cant detect it when the number has been 'guessed'.. does anyone know why?

I will greatly appreciate the help:)

Answer 1

You have numberHasBeenGuessed = True outside of the while loop - which means that it can't get called until the loop is over - so it will be forever stuck.

When it gets to your guess - lets say I have the number 7. Your program asks 'Is 7 smaller or larger than 7?' Obviously that makes no sense, 7 is 7. 7 is not smaller or larger than 7: and your program knows that and crashes. So you need to introduce a new user input option:

    import random
    
    maxNum = int(input('Enter the range: '))
    input('Think of a random number between 1 and ' + str(maxNum) + ' and press enter once done!')
    lowBound = 1
    highBound = maxNum
    response = ''
    noOfGuesses = 0
    numberHasBeenGuessed = False
    randomNumber = random.randint(lowBound,highBound)
    
    while not numberHasBeenGuessed:
        noOfGuesses += 1
        response = input("Is it smaller than " + str(randomNumber) + ", 'y', 'n', or 'Thats it'?")
        if response == "n" or response == 'N':
            lowBound = randomNumber + 1   
            randomNumber = random.randint(lowBound,highBound)
            print(randomNumber)
        elif response == "y" or response == "Y":
            highBound = randomNumber - 1
            randomNumber = random.randint(lowBound,highBound)
            print(randomNumber)
        elif response == "Thats it": #New input option 'Thats it'
            numberHasBeenGuessed = True #Stops the while loop
        else:
            print ('Please only type y, Y, n or N as responses')
               
    print('Wonderful it took me ' + str(noOfGuesses) + ' attempts to guess that you had the number ' + str(randomNumber) + ' in mind')

Now, you can input 'Thats it' when your number is guessed and the program finishes with the output you want. (Of course, change the inputs and what not to what you want)

Also final programmer tip: comment your code with hashtags, so you know (and others helping) what each part does.

Answer 2

Here is a version using try/except

import random

maxNum = int(input('Enter the range: '))
input('Think of a random number between 1 and ' + str(maxNum) + ' and press enter once done!')
lowBound = 1
highBound = maxNum
response = ''
noOfGuesses = 0
numberHasBeenGuessed = False
randomNumber = random.randint(lowBound,highBound)

while not numberHasBeenGuessed:
        noOfGuesses += 1
        response = input("Is it smaller than " + str(randomNumber) + ", 'y', 'n', or 'Thats it'?")
        if response == "n" or response == 'N':
            lowBound = randomNumber + 1
            
            try:
                randomNumber = random.randint(lowBound,highBound)
            except ValueError:
                numberHasBeenGuessed = True
        elif response == "y" or response == "Y":
            highBound = randomNumber - 1

            try:
                randomNumber = random.randint(lowBound,highBound)
            except ValueError:
                numberHasBeenGuessed = True
        else:
            print ('Please only type y, Y, n or N as responses')
        
           
print('Wonderful it took me ' + str(noOfGuesses) + ' attempts to guess that you had the number ' + str(randomNumber) + ' in mind')

When it encounters a ValueError , it will take it that it has found your number. Please make sure there are no other situations that can result in an incorrect answer with this code, as I obviously haven't tested it thoroughly.

You could also put the try/except clauses in a def to make it more compact as they are the same pieces of code, but I wasn't sure if that was allowed or not for your project, so I left it.