Vertex covering by paths on trees with its applications in machine translation
نویسندگان
چکیده
Given a tree and a set of paths in the tree, the problem of finding a minimum number of paths from the given path set to cover all the vertices in the tree is investigated in the paper. To distinguish from the classical path cover problem, such an optimization problem is referred to as vertex covering by paths. The problem and its edge variant, edge covering by paths, find applications in machine translation. Complexity and algorithmic results are presented for the problem and its edge variant.
منابع مشابه
Two fixed-parameter algorithms for Vertex Covering by Paths on Trees
Vertex Covering by Paths on Trees with applications in machine translation is the task to cover all vertices of a tree T = (V,E) by choosing a minimum-weight subset of given paths in the tree. The problem is NP-hard and has recently been solved by an exact algorithm running in O(4 · |V |2) time, where C denotes the maximum number of paths covering a tree vertex. We improve this running time to ...
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ورودعنوان ژورنال:
- Inf. Process. Lett.
دوره 97 شماره
صفحات -
تاریخ انتشار 2006