A strongly polynomial algorithm for the inverse shortest arborescence problem
نویسندگان
چکیده
منابع مشابه
A Strongly Polynomial Algorithm for the Inverse Shortest Arborescence Problem
In this paper an inverse problem of the weighted shortest arborescence problem is discussed. That is. given a directed graph G and a set of nonnegative costs on its arcs. we need to modify those costs as little as possible to ensure that T, a given (.I-arborescence of G, is the shortest one. It is found that only the cost of T needs modifying. An O(rz”) combinatorial algorithm is then proposed....
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15 صفحه اولInverse scattering problem for the Impulsive Schrodinger equation with a polynomial spectral dependence in the potential
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Abst ract Given a set N of n terminals in the rst quadrant of the Euclidean plane E 2 , nd a minimum length directed tree rooted at the origin o, connecting to all terminals in N, and consisting of only horiz on tal and vertical arcs oriented from left to right or from bottom to top. This problem is called rectilinear Steiner arborescence problem. which has been proved to be NP-complete recentl...
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ژورنال
عنوان ژورنال: Discrete Applied Mathematics
سال: 1998
ISSN: 0166-218X
DOI: 10.1016/s0166-218x(97)86750-9