Lecture 12 ( Submodular function 3 )
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چکیده
Lemma 1. f is submodular function. Proof. Let X, Y, Z ⊆ V , and u, v ∈ V be X = Z ∪ {u}, Y = Z ∪ {v}, v ∈ V , and e′(v) be the number of outgoing edges of u toward any vertices of Z. Let m be the number of connected components which are connected to u, but not connected to Z and b, and n be the number of connected components which are connected to v, but not connected to Z and u. 1. There are no edges between u and v, and no vertices which are connected to both u and v.
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تاریخ انتشار 2006