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Parallel Algorithms: Difference between revisions

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The first connectivity algorithm consists of <math>\log(n)</math> iterations of the following two steps:
The first connectivity algorithm consists of <math>\log(n)</math> iterations of the following two steps:
* Hookings - Each root hooks itself the the minimal adjacent root
* Hookings - Each root hooks itself the the minimal adjacent root. If there are no adjacent stars, then this rooted star quits.
* Parallel pointer jumping - Each vertex performs pointer jumping until every vertex points to the root, forming a rooted star.
* Parallel pointer jumping - Each vertex performs pointer jumping until every vertex points to the root, forming a rooted star.
;Theorems
# The pointer graph always consists of rooted trees.
# After <math>\log n</math> iterations, all vertices are contained in rooted stars that quit.
#: Each connected component is represented by a single rooted star.


;Complexity
;Complexity