<?xml version="1.0" encoding="UTF-8"?>

<record version="4" id="2939">
 <title>matching</title>
 <name>Matching</name>
 <created>2002-05-26 03:06:56</created>
 <modified>2006-09-27 22:55:45</modified>
 <type>Definition</type>
 <creator id="13753" name="Mathprof"/>
 <author id="13753" name="Mathprof"/>
 <author id="22" name="vampyr"/>
 <classification>
	<category scheme="msc" code="05C70"/>
 </classification>
 <defines>
	<concept>maximal matching</concept>
	<concept>perfect matching</concept>
 </defines>
 <related>
	<object name="MaximalMatchingminimalEdgeCoveringTheorem"/>
	<object name="Matching"/>
	<object name="EdgeCovering"/>
	<object name="Saturate"/>
 </related>
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\usepackage{amssymb}
\usepackage{amsmath}
\usepackage{amsfonts}

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 <content>Let $G$ be a graph.  A \emph{matching} $M$ on $G$ is a subset of the edges of $G$ such that each vertex in $G$ is incident with no more than one edge in $M$.

It is easy to find a matching on a graph; for example, the empty set will always be a matching.  Typically, the most interesting matchings are \emph{maximal matchings}.  A maximal matching on a graph $G$ is simply a matching of the largest possible size.

A \emph{perfect matching} is a matching that saturates every vertex.
</content>
</record>
