# DMGT

ISSN 1234-3099 (print version)

ISSN 2083-5892 (electronic version)

# IMPACT FACTOR 2018: 0.741

SCImago Journal Rank (SJR) 2018: 0.763

Rejection Rate (2017-2018): c. 84%

# Discussiones Mathematicae Graph Theory

## A LINEAR ALGORITHM FOR THE TWO PATHS PROBLEM ON PERMUTATION GRAPHS

C.P. Gopalakrishnan and C. Pandu Rangan

Department of Computer Science
Indian Institute of Technology

e-mail: rangan@iitm.ernet.in

## Abstract

The `two paths problem' is stated as follows. Given an undirected graph  G = (V,E)  and vertices  s1,t1;s2,t2, the problem is to determine whether or not  G  admits two vertex-disjoint paths  P1  and  P2  connecting  s1  with  t1  and  s2  with  t2  respectively. In this paper we give a linear (O(|V |+ |E |)) algorithm to solve the above problem on a permutation graph.

Keywords: algorithm, bridge, connectivity, disjoint paths, permutation graph, two paths problem.

1991 Mathematics Subject Classification: 05C38, 05C85.

## References

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