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Lecture 10 Matroid. Independent System. Consider a finite set S and a collection C of subsets of S. ( S , C ) is called an independent system if. i.e., it is hereditary. Each subset in C is called an independent set. Matroid. Matric Matroid. Graphic Matroid. Extension.
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Independent System • Consider a finite set S and a collection C of subsets of S. (S,C) is called an independent system if i.e., it is hereditary. Each subset in C is called an independent set.
Maximal Independent Set Theorem
About Matriod Theorem An independent system (S,C)is a matroid iff for any cost function c( ), the greedy algorithm MAX gives a maximum solution. Proof. (=>) Next, we show (<=).
Unit-time Task Scheduling Input Output
Independence Lemma Proof.
Matroid Theorem Proof
What we learnt in this lecture? • What is matroid?. • matric matroid and graphic matroid. • Relationship between matroid and greedy algorithm.