2024-07-20 20:21:08 +02:00
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---
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title: "Treap"
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date: 2024-07-20T14:12:27+01:00
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draft: false # I don't care for draft mode, git has branches for that
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description: "A simpler BST"
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tags:
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- algorithms
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- data structures
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- python
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categories:
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- programming
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series:
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- Cool algorithms
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favorite: false
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disable_feed: false
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graphviz: true
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---
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The [_Treap_][wiki] is a mix between a _Binary Search Tree_ and a _Heap_.
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Like a _Binary Search Tree_, it keeps an ordered set of keys in the shape of a
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tree, allowing for binary search traversal.
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Like a _Heap_, it associates each node with a priority, making sure that a
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parent's priority is always higher than any of its children.
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[wiki]: https://en.wikipedia.org/wiki/Treap
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<!--more-->
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2024-07-20 20:21:47 +02:00
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## What does it do?
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By randomizing the priority value of each key at insertion time, we ensure a
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high likelihook that the tree stays _roughly_ balanced, avoiding degenerating to
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unbalanced O(N) height.
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Here's a sample tree created by inserting integers from 0 to 250 into the tree:
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{{< graphviz file="treap.gv" />}}
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