Hitting Set Formulation
Set covering is equivalent to the hitting set problem. It is easy to see this by observing that an instance of set covering can be viewed as an arbitrary bipartite graph, with sets represented by vertices on the left, the universe represented by vertices on the right, and edges representing the inclusion of elements in sets. The task is then to find a minimum cardinality subset of left-vertices which covers all of the right-vertices. In the Hitting set problem, the objective is to cover the left-vertices using a minimum subset of the right vertices. Converting from one problem to the other is therefore achieved by interchanging the two sets of vertices.
Read more about this topic: Set Cover Problem
Famous quotes containing the words hitting, set and/or formulation:
“Can we not teach children, even as we protect them from victimization, that for them to become victimizers constitutes the greatest peril of all, specifically the sacrificephysical or psychologicalof the well-being of other people? And that destroying the life or safety of other people, through teasing, bullying, hitting or otherwise, putting them down, is as destructive to themselves as to their victims.”
—Lewis P. Lipsitt (20th century)
“He could walk, or rather turn about in his little garden, and feel more solid happiness from the flourishing of a cabbage or the growing of a turnip than was ever received from the most ostentatious show the vanity of man could possibly invent. He could delight himself with thinking, Here will I set such a root, because my Camilla likes it; here, such another, because it is my little Davids favorite.”
—Sarah Fielding (17101768)
“Art is an experience, not the formulation of a problem.”
—Lindsay Anderson (b. 1923)