[ninjastampe]

Hi there guys. I'm having a problem with an assignment given to me by my current python instructor (that would be my dad). He asked me to make a "reverse guessing game" as in Python being the one guessing your number. I have sort of broken it down into understandability (if that's even a word) for myself and maybe you other guys. This is NOT python code and is ONLY to help you understand it:

Start of loop
Program asks if it is larger than '(lowest number + highest number) / 2'
 If it is;
  'lowest number' = '(highest number + lowest number) / 2'
 If it is NOT;
  'highest number' -= 1

Program asks if it is smaller than '(lowest number + highest number) / 2'
 If it is;
  'highest number' = '(highest number + lowest number) / 2'
 If it is NOT;
  'smallest number' += 1
End of loop

now, I could write this, but I'm not sure if it's the most efficient way. Dad said, that it had to be the most efficient way of doing it.

Does any of you have an idea that you can break down for me?

(I'd rather code myself, no cheating )

This post has been edited by Dogstopper: 16 December 2010 - 04:26 PM

[Dogstopper]

I'd keep two pointers. Initially, the low-number pointer is at 0 and the high number of 101 (assuming the range is 1-100).

You can do something like this:

high = 101
low = 1

guess = (high-low)/2
while guess != number:
    if number > guess:
        low = guess
    elif number < guess:
        high = guess
    else
        print 'Your number is ' + str(guess)
    guess = (high-low)/2

[ninjastampe]

Thanks, I'll definately give it a try (in my own coding :

[Dogstopper]

I didn't actually mean to give that to you...I forgot this was a Python post...I use Python as my "pseudo code" in the Java forum

Anyway, hope the logic helps!

[ninjastampe]

It kinda did and it kinda didn't. Let me show you what I've got so far. When I run this, it just loops between outputting 50 and 75. But I'm going to bed now, and working further tomorrow. Anyways, you can try and run it if you want, see what happens.

import math
import os
os.system('title Pythons Inexpliccable Guessing Machine')
print "Hello there! Welcome to Pythons inexpliccable guessing machine! Let us start out right away!/n"
skippie=raw_input("If you know how to do this, enter skip ")
if skippie=="skip":
    n = 0
    while n <> 1:
        varmin=1
        varmax=100
        larger=raw_input("Is your input larger than " + str((varmin+varmax)/2) + " ")
        if larger == "yes" or "Yes":
            varmin= (varmin+varmax)/2
        if larger == "no" or "No":
            varmax += 1
            smaller=raw_input('Is your number smaller than ' + str((varmin+varmax)/2) + " ")
        if smaller == "yes" or "Yes":
            varmax=(varmax+varmin)/2
        else:
            varmin += 1

Edited by Dogstopper: !

This post has been edited by Dogstopper: 16 December 2010 - 06:04 PM

[Dogstopper]

I would do several things:
1) Change the loop to a boolean. It's easier to manage.
2) Pull the varmin and varmax OUT of the loop. You DON'T want to reset it every time.
3) Change your interface to accept 1 of 3 possible inputs, not 1 at a time (this simplifies things)
4) if larger or smaller, change the range.

Here is your code with those changes:

if skippie=="skip":

    found = False
    varmin=1
    varmax=100
    while not found:

        guess = (varmax+varmin)/2
        ans=raw_input("Is your input larger (l), smaller(s), or equal to (e) than " + str(guess) + " ")
        if ans == "L" or ans == "l":
            varmin = guess
        elif ans == "S" or ans == "s":
            varmax = guess
        else:
            print "Yay! I got it!"
            found = True

Here is a quote of my session (my number was 63:

Quote

Hello there! Welcome to Pythons inexpliccable guessing machine! Let us start out right away!/n
If you know how to do this, enter skip skip
Is your input larger (l), smaller(s), or equal to (e) than 50 l
Is your input larger (l), smaller(s), or equal to (e) than 75 s
Is your input larger (l), smaller(s), or equal to (e) than 62 l
Is your input larger (l), smaller(s), or equal to (e) than 68 s
Is your input larger (l), smaller(s), or equal to (e) than 65 s
Is your input larger (l), smaller(s), or equal to (e) than 63 e
Yay! I got it!

Finally, it's \n, not /n

[Steven Smith]

I think it would be appropriate to add entry validation to this as well. In its simplest form, add another elif for E/e, and use the else statement to ask the question again with a reminder to use a correct entry. Otherwise any keystroke other than L/l/S/s registers as a "found answer".

Steve

[ninjastampe]

Thank you awesomely much guys! I agree with Steve, that might be needed. Also, your thing ALMOST worked! The only thing it doesn't do is be able to guess 100. Try it out yourself, just press "l, l, l, l" it only goes to 99. So I changed varmax to 101, and now it works just fine. Love this site! Thank you guys.