[Tutor] Searching a text file's contents and comparing them toalist

Alan Gauld alan.gauld at btinternet.com
Wed Jul 14 21:32:10 CEST 2010

"Eric Hamiter" <ehamiter at gmail.com> wrote

> aisle_one = ["chips", "bread", "pretzels", "magazines"]
> aisle_two = ["juice", "ice cream"]
> aisle_three = ["asparagus"]
> def find_groceries():
>    grocery_list = open("grocery_list.txt", "r")
>    for line in grocery_list.readlines():

See previous about removing the redundant readlines()

>        line = line.strip()
>        if line in aisle_one:
>            first_run = "%s" % line + " - aisle one.\n"

The string formatting is redundant here since you assign a string to a 
You could just dio:

            first_run = line + " - aisle one.\n"

> I can see that the variables first_run, second_run and third_run are
> writing over themselves while looping, which is logical, but this is
> not what I want. If I simply print them immediately instead of 
> storing
> them as variables, all items will print, but not in the order I 
> wish.

So store the strings in a list then at the end print each list of 

> The ultimate goal of the program will be to sort the items based on
> aisle locations. Is there an efficient way to do this?

You can sort the lists before printing...

> I think I want some kind of incremental counter going on in the loop
> to prevent them from overwriting themselves, or a way to store
> multiple variables, but I'm not sure how to do that.

No need for counters, just append() to a list.

Alan Gauld
Author of the Learn to Program web site

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