Summary: Approximating the Spanning Star Forest Problem and Its Applications to
Genomic Sequence Alignment
C. Thach Nguyen
Jian Shen
Minmei Hou
Li Sheng§
Webb Miller¶
Louxin Zhang
Abstract
This paper studies the algorithmic issues of the span
ning star forest problem. We prove the following re
sults: (1) there is a polynomialtime approximation
scheme for planar unweighted graphs; (2) there is a
polynomialtime algorithm with approximation ratio 3
5
for unweighted graphs; (3) it is NPhard to approxi
mate the problem within ratio 545
546 + for unweighted
graphs; (4) there is a lineartime algorithm to compute
the maximum star forest of a weighted tree; (5) there is
