A Simple Solution to the Level-Ancestor Problem

Gaurav Menghani; Dhruv Matani

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arXiv · 1903.01387

A Simple Solution to the Level-Ancestor Problem

Gaurav Menghani·Dhruv Matani

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Abstract

A Level Ancestory query LA($u$, $d$) asks for the the ancestor of the node $u$ at a depth $d$. We present a simple solution, which pre-processes the tree in $O(n)$ time with $O(n)$ extra space, and answers the queries in $O(\log\ {n})$ time. Though other optimal algorithms exist, this is a simple enough solution that could be taught and implemented easily.

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BibTeX RIS

Gaurav Menghani, Dhruv Matani. 2019-03-04. A Simple Solution to the Level-Ancestor Problem. https://arxiv.org/abs/1903.01387

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