A simple optimal parallel algorithm to solve the lowest common ancestor problem
The problem of computing the lowest common ancestors of all pairs of nodes in a rooted tree is central in a large number of practical applications. The purpose of this note is to propose a very simple cost-optimal parallel algorithm to solve the lowest common ancestor problem. More precisely, with an n-node rooted tree as input, our algorithm runs in O(log n) time using O(n2/log n) processors in the EREW-PRAM model.
Key Wordsordered trees list ranking Euler tour lowest common ancestors parallel algorithms EREW-PRAM
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