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arXiv · 1412.8338

Maximum Cardinality Neighbourly Sets in Quadrilateral Free Graphs

Neethi K. S.·Sanjeev Saxena
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Abstract

Neighbourly set of a graph is a subset of edges which either share an end point or are joined by an edge of that graph. The maximum cardinality neighbourly set problem is known to be NP-complete for general graphs. Mahdian (M.Mahdian, On the computational complexity of strong edge coloring, Discrete Applied Mathematics, 118:239-248, 2002) proved that it is in polynomial time for quadrilateral-free graphs and proposed an O(n^{11}) algorithm for the same (along with a note that by a straightforward but lengthy argument it can be proved to be solvable in O(n^5) running time). In this paper we propose an O(n^2) time algorithm for finding a maximum cardinality neighbourly set in a quadrilateral-free graph.

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Neethi K. S., Sanjeev Saxena. 2014-12-29. Maximum Cardinality Neighbourly Sets in Quadrilateral Free Graphs. https://doi.org/10.1007/s10878-015-9972-9

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