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Re: How to remove item from heap efficiently?

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From srinivas devaki <mr.eightnoteight@gmail.com>
Newsgroups comp.lang.python
Subject Re: How to remove item from heap efficiently?
Date Fri, 8 Jan 2016 18:51:36 +0530
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You can create a single heap with primary key as timestamp and
secondary key as priority, i.e by creating a tuple
insert the elements into the heap as
(timestamp, priority)


If there is any underlying meaning for creating 2 heaps. please mention.


On Fri, Jan 8, 2016 at 4:22 AM, Sven R. Kunze <srkunze@mail.de> wrote:
> Hi everybody,
>
> suppose, I need items sorted by two criteria (say timestamp and priority).
> For that purpose, I use two heaps (heapq module):
>
> heapA # items sorted by timestamp
> heapB # items sorted by priority
>
> Now my actual problem. When popping an item of heapA (that's the oldest
> item), I need to remove the very same item from heapB, regardlessly where it
> is in heapB. And vice versa.
>
> Is there a datastructure or a simple trick to achieve that in an efficient
> matter?
>
> Best,
> Sven
> --
> https://mail.python.org/mailman/listinfo/python-list

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Re: How to remove item from heap efficiently? srinivas devaki <mr.eightnoteight@gmail.com> - 2016-01-08 18:51 +0530

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