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The.Algorithm.Design.Manual.Springer-Verlag.1998

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<strong>The</strong> Friendship Graph<br />

friendship graph would truly be the ultimate in social-ism.<br />

● What is the largest clique?<br />

A social clique is a group of mutual friends who all hang around together. A graph-theoretic<br />

clique is a complete subgraph, where each vertex pair has an edge between them. Cliques are the<br />

densest possible subgraphs. Within the friendship graph, we would expect to see large cliques<br />

corresponding to workplaces, neighborhoods, religious organizations, and schools.<br />

● How long will it take for my gossip to get back to me?<br />

A cycle is a path where the last vertex is adjacent to the first. A cycle in which no vertex repeats<br />

(such as 1-2-3-1 verus 1-2-3-2-1) is said to be simple. <strong>The</strong> shortest cycle in the graph defines the<br />

graph's girth, while a simple cycle that passes through every vertex once is said to be a<br />

Hamiltonian cycle. An undirected graph with no cycles is said to be a tree if it is connected;<br />

otherwise it is a forest. A directed graph with no directed cycles is said to be a DAG, or directed<br />

acyclic graph.<br />

Next: Data Structures for Graphs Up: Graph <strong>Algorithm</strong>s Previous: Graph <strong>Algorithm</strong>s<br />

<strong>Algorithm</strong>s<br />

Mon Jun 2 23:33:50 EDT 1997<br />

file:///E|/BOOK/BOOK2/NODE60.HTM (3 of 3) [19/1/2003 1:29:02]

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