A new parallel algorithm for rooting a tree

  • Taenam Kim
  • Dukhwan Oh
  • Eunki Lim


When an undirected tree,T, and a vertex,r, in the tree are given, the problem to transformT into a rooted tree withr as its root is considered. Using Euler tour and prefix sum, an optimal algorithm has been developed [2, 3]. We will present another parallel algorithm which is optimal also on EREW PRAM. Our approach reduces the given tree step by step by pruning and pointer jumping. That is, the tree structure is retained during algorithm processing such that another tree computations can be carried out in parallel.

AMS Mathematics Subject Classification

68Q22 68Q25 

Key word and phrases

parallel algorithms trees rooted trees PRAM model 


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Copyright information

© Korean Society for Computational and Applied Mathematics 1998

Authors and Affiliations

  1. 1.Department of Computer EngineeringKumoh National University of Technology Sinpyeongdong, KumisiKyeongbookKorea

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