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Python

Posted by Sabry Salman
Sabry Salman
2,465 Points

loop doesn't work - need help

I am trying to create a program where the user enters a letter (eg "D") and retrieves a name of names, from a LIST. I have two issues

  1. if user types "D" is only retrives on item in the list, when there are two
  2. if user does get the right item, it still runs the "else" section and print

what am I doing wrong? Thanks

see file with swith.py (https://w.trhou.se/dtygos96sc)

this program utilises the startswith() function

video_games = ["Destiny", "Origins", "Division"] cool_movies = ["Aliens", "Guardians", "Hitman"]

def ask_char(char, user_list): new_list =[] for string in user_list: if string.startswith(char): new_list.append(string) print(new_list)

    else:
        print("cant find your choice. See list available")
        print(video_games)
        break

char = input("what letter do you want, use uppercase? ") ask_char(char, video_games)

Steven Parker
Steven Parker
230,274 Points
Steven Parker
Steven Parker
230,274 Points

In Python, indentation is critical to understanding the code, and it may be responsible for your issue.

Use the instructions for code formatting in the Markdown Cheatsheet pop-up below the "Add an Answer" area. :arrow_heading_down:
Or watch this video on code formatting.

1 Answer

Sebastiaan van Vugt
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Sebastiaan van Vugt
Python Development Techdegree Graduate 13,554 Points
Sebastiaan van Vugt
.a{fill-rule:evenodd;}techdegree seal-36
Sebastiaan van Vugt
Python Development Techdegree Graduate 13,554 Points

Hello Sabry. You're on the right way and you will find your code making more sense with a few small adjustments.

Right now input "D" will result in the list video_games to be searched one string at a time. Since "Destiny" starts with a "D" it will add this to the new_list and then print it. On the first round, the else will therefore not fire. On the second round, however "else" will be activated since Origin does not start with a "D". It will print the feedback message, the whole list of video games (instead of the new list) and then break out of the loop.

What you probably want to do is remove all printouts and the else section (alternatively you could also change the break to a continue), use a second if statement after the first to test if the list is empty or not and then print either the new_list or a message saying that the list does not contain words starting with the specified letter. This way every string will be checked and added to the new_list if it starts with the desired character and the result will be based on the list as a whole.

I hope this helps. Do let me know if you have further questions.

PS. I agree with Steven on the formatting (it's faster to read with the right formatting) but could luckily open the workspace file.