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CSC 263H               Tutorial Outline for Week 12             Winter 2004
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BFS
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For any two vertices u,v in a graph, let delta(u,v) represent the number of
edges on a shortest path from u to v (i.e., a path with the smallest number
of edges).
Prove that at the end of BFS (started from vertex s), d[v] = delta(s,v),
the number of edges on a shortest path from s to v.