Sequential and Parallel Algorithms for Finding a Longest Non-negative Path in a Tree

트리에서 가장 긴 비음수 경로를 찾는 직렬 및 병렬 알고리즘

  • Published : 2006.12.15

Abstract

In an edge-weighted(positive, negative, or zero weights are possible) tree, we want to solve the problem of finding a longest path such that the sum of the weights of the edges in tile path is non-negative. To find a longest non-negative path of a tree we present a sequential algorithm with O(n logn) time and a CREW PRAM parallel algorithm with $O(log^2n)$ time and O(n) processors. where n is the number of nodes in the tree.

각 에지에 무게(양수, 음수, 0 가능)가 주어진 트리에서, 경로의 에지들의 무게의 합이 비음수이면서 길이가 가장 긴 경로를 구하는 문제를 해결하고자 한다. 트리에서 가장 긴 비음수 경로를 찾는 O(n logn) 시간 직렬 알고리즘과 $O(log^2n)$ 시간과 O(n)개의 프로세서를 사용하는 CREW PRAM 병렬 알고리즘을 제시한다. 여기서, n은 트리가 가지는 노드의 수이다.

Keywords

References

  1. L. Allison, Longest biased intervals and longest non-negative sum intervals, Bioinformatics, vol. 19(10), pp. 1294-1295, 2003 https://doi.org/10.1093/bioinformatics/btg135
  2. L. Wang and Y. Xu, SEGID: Identifying interesting segments in (multiple) sequence alignments, Bioinformatics, vol. 19(2), pp. 297-298, 2003 https://doi.org/10.1093/bioinformatics/19.2.297
  3. B.Y. Wu, K.-M. Chao, and C.Y. Tang, An efficient algorithm for the length-constrained heaviest path problem on a tree, Information Processing Letters, vol. 69, pp. 63-67, 1999 https://doi.org/10.1016/S0020-0190(98)00194-X
  4. S.K. Kim, Finding a longest nonnegative path in a constant degree tree, Information Processing Letters, vol. 93, no. 6, pp. 275-279, March 2005 https://doi.org/10.1016/j.ipl.2004.11.012
  5. J. JaJa, An Introduction to Parallel Algorithms, Addison-Wesley, 1992
  6. D.E. Knuth, The Art of Programming, Vol. 1. Fundamental Algorithms, 2nd Edition, Addison-Wesley, 1973
  7. H. Shen, Fast parallel algorithm for finding kth longest path in a tree, Proceedings of the 1997 Advances in Parallel and Distributed Computing Conference (APDC '97), IEEE, pp. 164-169, 1997 https://doi.org/10.1109/APDC.1997.574028