Tractability of Parameterized Completion Problems on Chordal, Strongly Chordal, and Proper Interval Graphs

  • Authors:
  • Haim Kaplan;Ron Shamir;Robert E. Tarjan

  • Affiliations:
  • -;-;-

  • Venue:
  • SIAM Journal on Computing
  • Year:
  • 1999

Quantified Score

Hi-index 0.00

Visualization

Abstract

We study the parameterized complexity of three NP-hard graph completion problems.The minimum fill-in problem asks if a graph can be triangulated by adding at most k edges. We develop O(ck m) and O(k2mn+f(k)) algorithms for this problem on a graph with n vertices and m edges. Here f(k) is exponential in k and the constants hidden by the big-O notation are small and do not depend on k. In particular, this implies that the problem is fixed-parameter tractable (FPT).The proper interval graph completion problem, motivated by molecular biology, asks if a graph can be made proper interval by adding no more than k edges. We show that the problem is FPT by providing a simple search-tree-based algorithm that solves it in O(ck m)-time. Similarly, we show that the parameterized version of the strongly chordal graph completion problem is FPT by giving an O(ck m log n)-time algorithm for it.All of our algorithms can actually enumerate all possible k-completions within the same time bounds.