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Re: How to remove item from heap efficiently?

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Thanks for your suggestion.

On 08.01.2016 14:21, srinivas devaki wrote:
> 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)
I think I cannot use that because I need the list sorted by both criteria.
> If there is any underlying meaning for creating 2 heaps. please mention.

I use two heaps because I need to insert arbitrary items fast and remove 
the ones fast which are too old (timestamp) or are next in order (priority).

Basically a task scheduler where tasks can be thrown away once they are 
too long in the queue.

> 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? "Sven R. Kunze" <srkunze@mail.de> - 2016-01-08 17:45 +0100
  Re: How to remove item from heap efficiently? Paul Rubin <no.email@nospam.invalid> - 2016-01-09 10:32 -0800
    Re: How to remove item from heap efficiently? "Sven R. Kunze" <srkunze@mail.de> - 2016-01-10 19:50 +0100
    Re: How to remove item from heap efficiently? srinivas devaki <mr.eightnoteight@gmail.com> - 2016-01-12 08:38 +0530
      Re: How to remove item from heap efficiently? Paul Rubin <no.email@nospam.invalid> - 2016-01-11 19:16 -0800

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