Tree spanners on chordal graphs: complexity and algorithms
نویسندگان
چکیده
منابع مشابه
Tree spanners on chordal graphs: complexity and algorithms
A tree t-spanner T in a graph G is a spanning tree of G such that the distance in T between every pair of vertices is at most t times their distance in G. The TREE t-SPANNER problem asks whether a graph admits a tree t-spanner, given t. We substantially strengthen the hardness result of Cai and Corneil (SIAM J. Discrete Math. 8 (1995) 359–387) by showing that, for any t¿ 4, TREE t-SPANNER is NP...
متن کاملTree Spanners on Chordal Graphs: Complexity, Algorithms, Open Problems
A tree t-spanner T in a graph G is a spanning tree of G such that the distance in T between every pair of vertices is at most t times their distance in G. The Tree t-Spanner problem asks whether a graph admits a tree t-spanner, given t. We substantially strengthen the hardness result of Cai and Corneil [SIAM J. Discrete Math. 8 (1995) 359– 387] by showing that, for any t ≥ 4, Tree t-Spanner is ...
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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 2004
ISSN: 0304-3975
DOI: 10.1016/s0304-3975(03)00424-9