Question

I’m trying to write a python program in which the program guesses the users number. I fel like an idiot, the part i am getting caught up on is the math, i feel like its one of those things where I’ve been working on it for a few hours and someone else would be able to bring a fresh perspective and solve it easily. I figured to start off I would take the user component out of it almost completely. Here is what I have so far, its getting stuck on the logic part and eventually just keeps saying its either too low or too high, for infinity:

MIN=0
MAX=100
firstguess = MAX - MIN
firstguess = firstguess/2

while 1==1:
number = int(raw_input("Enter your number 0-100:"))
print firstguess
oldguess = firstguess
if firstguess > number:
    print "First guess is too high."
    raw_input()
    guess = int(25)
    print guess
    while guess != number:
        if guess > number:
            print "My guess was too high."
            raw_input()
            nextguess = oldguess - guess
            nextguess = nextguess/2
            nextguess = guess - nextguess
            oldguess = guess
            guess = nextguess
        elif guess == number:
            print "I win!"
            exit
        elif guess < number:
            print "My guess was too low."
            raw_input()
            nextguess = oldguess - guess
            nextguess = nextguess/2
            nextguess = nextguess + guess
            oldguess = guess
            guess = nextguess
elif firstguess == number:
    print "I win!"
elif firstguess < number:
    print "My first guess was too low."
    raw_input()
    guess = 75
    print guess
    print guess
    while guess != number:
        if guess > number:
            print "My guess was too high."
            raw_input()
            nextguess = oldguess - guess
            nextguess = nextguess/2
            nextguess = guess - nextguess
            oldguess = guess
            guess = nextguess
        elif guess == number:
            print "I win!"
            exit
        elif guess < number:
            print "My guess was too low."
            raw_input()
            nextguess = oldguess - guess
            nextguess = nextguess/2
            nextguess = nextguess + guess
            oldguess = guess
            guess = nextguess

Answer 1

I might be doing your homework, but you seemed to make an honest attempt at the problem:

bounds = [0, 100]
minimum, maximum = bounds

number = int(raw_input('Pick a number [{0}-{1}]: '.format(minimum, maximum)))

while guess != number:
  guess = int((maximum + minimum) / 2)
  raw_input('Guessing {0}'.format(guess))

  if guess > number:
    maximum = guess
  elif guess < number:
    maximum = bounds[1]
    minimum = guess

print 'I win!'

The logic is simple:

1. Choose lower and upper bounds for the guesses.
2. Have the user pick a number, stored as number.
3. While the guess is not equal to the number:
   1. Choose the midpoint between the minimum and maximum range bounds.
   2. If the guess is bigger than the number, then the number must be smaller than the guess, so we set the maximum guess bound to be the current guess.
   3. If the guess is smaller than the number, then we set the maximum to be the highest number possible and the minimum to be the guess.
4. Once the guess is the number, the loop breaks and we win.