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The level ancestor problem simplified. (English) Zbl 1068.68047
Summary: We present a simple algorithm for the Level Ancestor Problem. A Level Ancestor Query LA($$v,d$$) requests the depth $$d$$ ancestor of node $$v$$. The Level Ancestor Problem is to preprocess a given rooted tree $$T$$ to support level ancestor queries. While optimal solutions to this problem already exist, our new optimal solution is simple enough to be taught and implemented.

##### MSC:
 68P05 Data structures 05C05 Trees
##### Keywords:
Data structures; Rooted trees; Level Ancestor Problem
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##### References:
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