Title
An algorithm for road coloring
Abstract
A coloring of edges of a finite directed graph turns the graph into a finite-state automaton. The synchronizing word of a deterministic automaton is a word in the alphabet of colors (considered as letters) of its edges that maps the automaton to a single state. A coloring of edges of a directed graph of uniform outdegree (constant outdegree of any vertex) is synchronizing if the coloring turns the graph into a deterministic finite automaton possessing a synchronizing word. The road coloring problem is the problem of synchronizing coloring of a directed finite strongly connected graph of uniform outdegree if the greatest common divisor of the lengths of all its cycles is one. The problem posed in 1970 has evoked noticeable interest among the specialists in the theory of graphs, automata, codes, symbolic dynamics as well as among the wide mathematical community. A polynomial time algorithm of O(n3) complexity in the worst case and quadratic in the majority of studied cases for the road coloring of the considered graph is presented below. The work is based on the recent positive solution of the road coloring problem. The algorithm was implemented in the freeware package TESTAS.
Year
DOI
Venue
2012
10.1016/j.jda.2012.05.003
Journal of Discrete Algorithms
Keywords
DocType
Volume
finite-state automaton,cubic worst-case time complexity,deterministic automaton,constant outdegree,synchronizing coloring,corresponding deterministic finite automaton,quadratic time complexity,considered graph,deterministic finite automaton,road coloring,freeware package,synchronizing word,polynomial time algorithm,uniform outdegree,directed graph,symbolic dynamics,discrete mathematics,finite state automaton,connected graph,algorithm,greatest common divisor,synchronization,graph
Journal
16,
ISSN
Citations 
PageRank 
1570-8667
3
0.53
References 
Authors
16
1
Name
Order
Citations
PageRank
A. N. Trahtman19211.68