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From: "Sven R. Kunze" <srkunze@mail.de>
Newsgroups: comp.lang.python
Subject: How to remove item from heap efficiently?
Date: Thu, 7 Jan 2016 23:52:48 +0100
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Xref: csiph.com comp.lang.python:101372

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