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Python

Posted by Mohamed THIAM
Mohamed THIAM
1,091 Points

Second Shopping list App

Hello everyone,

So I did the Second Shopping list App challenge and got it to work without using functions, ELIFs or ELSEs. FOR some reason, the moment I do things stop working.

Can someone please walk me through optimizing my code?

Thanks!

shopping_list = []

print('What would you like to add to your list?')
print('Enter DONE when you are finished adding items.')
print('Enter HELP for assistance.')
print('Enter SHOW to see all your current items.')

while True:
    new_item = input('> ')

    if new_item == 'DONE':
        break

    shopping_list.append(new_item)

    if new_item == 'HELP':
        shopping_list.remove('HELP')
        print('Add an item to your list and enter DONE when you are finished.')

    if new_item == 'SHOW':
        print('Here are your current items: ')

        shopping_list.remove('SHOW')

        for item in shopping_list:
            print(item)

print('Here is your list of items:')

for item in shopping_list:
    print(item)

Here is a second attempt:

shopping_list = []

print('What would you like to add to your list?')


def show_help():
    print('''Enter DONE when you are finished adding items.
Enter HELP for assistance.
Enter SHOW to see all your current items.''')


def show_list():
    print('Here are your current items: ')
    for item in shopping_list:
        print(item)


def main():
    while True:
        new_item = input('> ')

        if new_item == 'DONE':
            break

        shopping_list.append(new_item)

        if new_item == 'HELP':
            shopping_list.remove('HELP')
            show_help()

        if new_item == 'SHOW':
            shopping_list.remove('SHOW')
            show_list()

    print('Here is your list of items:')

    for item in shopping_list:
        print(item)


show_help()

main()

[MOD: added python to the markdown formatting -cf]

2 Answers

Mohamed THIAM
Mohamed THIAM
1,091 Points
Mohamed THIAM
Mohamed THIAM
1,091 Points

This is awesome Andreas. I'm still figuring out my code hierarchy. Sometimes, it's the reason my script doesn't run. You made it very clear. Thanks for taking the time.

Mo.

Andreas cormack
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Andreas cormack
Python Web Development Techdegree Graduate 33,011 Points
Andreas cormack
.a{fill-rule:evenodd;}techdegree seal-36
Andreas cormack
Python Web Development Techdegree Graduate 33,011 Points

Hi Mohamed

Elif works for me, also if you append the new item's to the list at the end after all the conditions are accounted for you wont need to remove help and show from the list. Also you dont need the while loop inside a function called main.

shopping_list = []

print('What would you like to add to your list?')


def show_help():
    print('''
          Enter DONE when you are finished adding items.
          Enter HELP for assistance.
          Enter SHOW to see all your current items.''')


def show_list():
    print('Here are your current items: ')
    for item in shopping_list:
        print(item)


while True:
  new_item = input('> ')

  if new_item == 'DONE':
    break

  elif new_item == 'HELP':
    show_help()
    continue

  elif new_item == 'SHOW':
    show_list()
    continue

  shopping_list.append(new_item) 

show_list()