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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
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