How to add/drop items from a list

Question

I see plenty of posts adding and subtracting strings from a list but I need help with keeping count of those items.

I would like to couple those items so there are no repeats just a counter.

Ex: 3 Apples 4 Oranges 2 Bananas

I want to be able to "take" one item at a time so if I were to call: "take Apple" and I were to check my inventory then, I would have: 2 Apples 4 Oranges 2 Bananas

I would also like to do the opposite. I would like to "drop" an item and have it added to the inventory in the room.

Right now I only know how to pick up ALL of the apples at once and not just 1 at a time. Also, my items are loaded into the program from a separate txt file which is where all the items for each room are kept.

Craig Burgler Craig Burgler · Accepted Answer · 2016-08-25T04:17:14

Consider using a dictionary instead of a list. Dictionaries are ideal for maintaining counts of things:

from random import choice

def get_rooms(file_name):
    rooms = {}
    with open(file_name) as f:
        for l in f:
            room = l.split()
            room_number = int(room[0])
            rooms[room_number] = {} 
            for index, data in enumerate(room[1:], 1):
                if index % 2:
                    item = data
                else:
                    rooms[room_number][item] = int(data)
    return rooms

def generate_tests(number_of_test_actions):
    tests = []
    for _ in range(number_of_test_actions):
        tests.append((choice([1,2,3,4,5,6]),
                      choice(['Apple', 'Sword', 'Bow', 'Arrow', 'monkey']),
                      choice(['take', 'drop'])))
    return tests

def take_item(room, item):
    # generates and propagates KeyError exception if item not in room
    room[item] -= 1
    if not room[item]:
        room.pop(item)

def drop_item(room, item):
    if item in room:
        room[item] += 1
    else:
        room[item] = 1

rooms = get_rooms("rooms.txt")
for room, item, action in generate_tests(10):
    if action == 'take':
        print('taking', item, 'from room', room, ':', rooms[room])
        try:
            take_item(rooms[room], item)
        except KeyError:
            print('-- Sorry, no', item, 'in room', room, 'to take')
        else:
            print('-- took', item, 'from room', room, ':', rooms[room])                
    elif action == 'drop':
        print('dropping', item, 'in room', room, ':', rooms[room])
        drop_item(rooms[room], item)
        print('-- dropped', item, 'in room', room, ':', rooms[room])

rooms.txt

1 Sword 1 Apple 2
2 Apple 3
3 Bow 1 Arrow 3
4 Arrow 5
5 Bow 1
6 Arrow 10

Output

taking Apple from room 3 : {'Arrow': 3, 'Bow': 1}
-- Sorry, no Apple in room 3 to take
taking Apple from room 4 : {'Arrow': 5}
-- Sorry, no Apple in room 4 to take
dropping monkey in room 6 : {'Arrow': 10}
-- dropped monkey in room 6 : {'monkey': 1, 'Arrow': 10}
dropping Apple in room 5 : {'Bow': 1}
-- dropped Apple in room 5 : {'Apple': 1, 'Bow': 1}
taking Bow from room 3 : {'Arrow': 3, 'Bow': 1}
-- took Bow from room 3 : {'Arrow': 3}
dropping monkey in room 3 : {'Arrow': 3}
-- dropped monkey in room 3 : {'monkey': 1, 'Arrow': 3}
dropping Arrow in room 6 : {'monkey': 1, 'Arrow': 10}
-- dropped Arrow in room 6 : {'monkey': 1, 'Arrow': 11}
taking Bow from room 5 : {'Apple': 1, 'Bow': 1}
-- took Bow from room 5 : {'Apple': 1}
taking Bow from room 4 : {'Arrow': 5}
-- Sorry, no Bow in room 4 to take
taking Bow from room 5 : {'Apple': 1}
-- Sorry, no Bow in room 5 to take

How to add/drop items from a list

1 Answers