######################################################## # # Animal # # From: Basic computer Games(1978) # # Unlike other computer games in which the computer # picks a number or letter and you must guess what it is, # in this game you think of an animal and the computer asks # you questions and tries to guess the name of your animal. # If the computer guesses incorrectly, it will ask you for a # question that differentiates the animal it guessed # from the one you were thinking of. In this way the # computer "learns" new animals. Questions to differentiate # new animals should be input without a question mark. # This version of the game does not have a SAVE feature. # If your sistem allows, you may modify the program to # save array A$, then reload the array when you want # to play the game again. This way you can save what the # computer learns over a series of games. # At any time if you reply 'LIST' to the question "ARE YOU # THINKING OF AN ANIMAL", the computer will tell you all the # animals it knows so far. # The program starts originally by knowing only FISH and BIRD. # As you build up a file of animals you should use broad, # general questions first and then narrow down to more specific # ones with later animals. For example, If an elephant was to be # your first animal, the computer would ask for a question to distinguish # an elephant from a bird. Naturally there are hundreds of possibilities, # however, if you plan to build a large file of animals a good question # would be "IS IT A MAMAL". # This program can be easily modified to deal with categories of # things other than animals by simply modifying the initial data # in Line 530 and the dialogue references to animal in Lines 10, # 40, 50, 130, 230, 240 and 600. In an educational environment, this # would be a valuable program to teach the distinguishing chacteristics # of many classes of objects -- rock formations, geography, marine life, # cell structures, etc. # Originally developed by Arthur Luehrmann at Dartmouth College, # Animal was subsequently shortened and modified by Nathan Teichholtz at # DEC and Steve North at Creative Computing # ######################################################## class Node: """ Node of the binary tree of questions. """ def __init__(self, text, yes_node, no_node): # the nodes that are leafs have as text the animal's name, otherwise # a yes/no question self.text = text self.yes_node = yes_node self.no_node = no_node def update_node(self, new_question, answer_new_ques, new_animal): # update the leaf with a question old_animal = self.text # we replace the animal with a new question self.text = new_question if answer_new_ques == 'y': self.yes_node = Node(new_animal, None, None) self.no_node = Node(old_animal, None, None) else: self.yes_node = Node(old_animal, None, None) self.no_node = Node(new_animal, None, None) # the leafs have as children None def is_leaf(self): return self.yes_node == None and self.no_node == None def list_known_animals(root_node): # Traversing the tree by recursion until we reach the leafs if root_node == None: return if root_node.is_leaf(): print(root_node.text, end=' '*11) return if root_node.yes_node: list_known_animals(root_node.yes_node) if root_node.no_node: list_known_animals(root_node.no_node) def parse_input(message, check_list, root_node): # only accepts yes or no inputs and recognizes list operation correct_input = False while not correct_input: try: inp = input(message) if check_list and inp.lower() == 'list': print('Animals I already know are:') list_known_animals(root_node) print('\n') token = inp[0].lower() if token == 'y' or token == 'n': correct_input = True except IndexError: pass return token def avoid_void_input(message): answer = '' while answer == '': answer = input(message) return answer def initial_message(): print(' '*32 + 'Animal') print(' '*15 + 'Creative Computing Morristown, New Jersey\n') print('Play ´Guess the Animal´') print('Think of an animal and the computer will try to guess it.\n') # Initial tree yes_child = Node('Fish', None, None) no_child = Node('Bird', None, None) root = Node('Does it swim?', yes_child, no_child) # Main loop of game initial_message() keep_playing = parse_input( 'Are you thinking of an animal? ', True, root) == 'y' while keep_playing: keep_asking = True # Start traversing the tree by the root actual_node = root while keep_asking: if not actual_node.is_leaf(): # we have to keep asking i.e. traversing nodes answer = parse_input(actual_node.text, False, None) if answer == 'y': actual_node = actual_node.yes_node else: actual_node = actual_node.no_node else: # we have reached a possible answer answer = parse_input('Is it a {}? '.format( actual_node.text), False, None) if answer == 'n': # add the new animal to the tree new_animal = avoid_void_input( 'The animal you were thinking of was a ? ') new_question = avoid_void_input( 'Please type in a question that would distinguish a {} from a {}: '.format(new_animal, actual_node.text)) answer_new_question = parse_input( 'for a {} the answer would be: '.format(new_animal), False, None) actual_node.update_node( new_question+'?', answer_new_question, new_animal) else: print("Why not try another animal?") keep_asking = False keep_playing = parse_input( 'Are you thinking of an animal? ', True, root) == 'y' ######################################################## # Porting Notes # # The data structure used for storing questions and # animals is a binary tree where each non-leaf node # has a question, while the leafs store the animals. # # As the original program, this program doesn't store # old questions and animals. A good modification would # be to add a database to store the tree. # Also as the original program, this one can be easily # modified to not only make guesses about animals, by # modyfing the initial data of the tree, the questions # that are asked to the user and the initial message # function (Lines 120 to 130, 135, 158, 160, 168, 173) ########################################################