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Re: Iterating through set

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On Mon, Jul 14, 2014 at 5:10 PM, LJ <luisjosenovoa@gmail.com> wrote:

> Hi All.
>
> I'm coding a Dynamic Programming algorithm to solve a network flow
> problem. At some point in the algorithm I have to iterate through a set of
> nodes, while adding and/or removing elements, until the set is empty. I
> know a regular set() object does not work in a case like this, so I wonder
> if anyone knows of an efficient pythonic way to handle this.
>

Your description of your need is somewhat vague, but this sounds like a
queue/stack which should be handled with a while loop and poping items.

Something like (untested):
mySet = [] # Typically, this would be a list. If you only want items
processed once per iteration, you'd likely use a separate set, however the
exact structure would vary based on the data and use-case.
# Some code to add initial items.
while mySet:
    item = mySet.pop()
    # Do something with item, which may call mySet.add(), and possibly
mySet.remove().


> Thanks in advance!
> --
> https://mail.python.org/mailman/listinfo/python-list
>

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Thread

Iterating through set LJ <luisjosenovoa@gmail.com> - 2014-07-14 17:10 -0700
  Re: Iterating through set Roy Smith <roy@panix.com> - 2014-07-14 20:30 -0400
  Re: Iterating through set Chris Kaynor <ckaynor@zindagigames.com> - 2014-07-14 18:08 -0700
  Re: Iterating through set Thomas Rachel <nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa915@spamschutz.glglgl.de> - 2014-07-17 15:22 +0200

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