CS 1 Lab 2 Part B

import random

def make_random_code():
    '''Returns a string of exactly four characters, each of which should be one
    of 'R', 'G', 'B', 'Y', 'O', or 'W'.'''
    colors = ['R', 'G', 'B', 'Y', 'O', 'W']
    code = ''
    i = 0
    while i < 4:
        code += random.choice(colors)
        i += 1
    return code

def count_exact_matches(str1, str2):
    '''Takes two arguments, both strings of length 4.  Returns the number of
    places where the two strings have the exact same letters at the exact same
    locations.'''
    count = 0
    for i in range(len(str1)):
        if str1[i] == str2[i]:
            count += 1
    return count

def count_letter_matches(str1, str2):
    '''Takes two arguments, both strings of length 4.  Returns the number of
    letters used in both strings regardless of location.'''
    lst1 = list(str1)
    lst2 = list(str2)
    count = 0
    for letter in lst1:
        if letter in lst2:
            count += 1
            lst2.remove(letter)
    return count

def compare_codes(code, guess):
    '''Takes two arguments, both strings of length 4.  Returns a string composed
    of the characters "b" (representing a match of both letter and position),
    "w" (representing a match of letter but not of position) and "-"
    (representing no match).'''
    count_black = count_exact_matches(code, guess)
    count_white = count_letter_matches(code, guess) \
                                            - count_exact_matches(code, guess)
    count_blank = 4 - (count_black + count_white)
    hint = ''
    hint += 'b' * count_black
    hint += 'w' * count_white
    hint += '-' * count_blank
    return hint

def run_game():
    print 'New game.'
    code = make_random_code()
    count = 0
    while True:
        guess = raw_input('Enter your guess: ')
        hint = compare_codes(code, guess)
        print '          Result: %s' % hint
        count += 1
        if hint == 'bbbb':
            print 'Congratulations!  You cracked the code in %d moves!' % count
            break