منابع مشابه
Almost All Friendly Matrices Have Many Obstructions
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We continue the research on the eeects of Monge structures in the area of combinatorial optimization. We show that three optimization problems become easy if the underlying cost matrix fulllls the Monge property: (A) The balanced max{cut problem, (B) the problem of computing minimum weight binary k-matchings and (C) the computation of longest paths in bipartite, edge-weighted graphs. In all thr...
متن کاملSubmatrix maximum queries in Monge matrices and Monge partial matrices, and their applications
We describe a data structure for submatrix maximum queries in Monge matrices or Monge partial matrices, where a query specifies a contiguous submatrix of the given matrix, and its output is the maximum element of that submatrix. Our data structure for an n × n Monge matrix takes O(n log n) space, O(n log n) preprocessing time, and can answer queries in O(log n) time. For a Monge partial matrix ...
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An II x m matrix A is called bottleneck Monge matrix if max{ajj, a,,} < max{a,, ali} for all l<i<r<n, 1 < j < s < m. The matrix A is termed permuted bottleneck Monge matrix, if there exist row and column permutations such that the permuted matrix becomes a bottleneck Monge matrix. We first deal with the special case of Cl bottleneck Monge matrices. Next, we derive several fundamental properties...
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ژورنال
عنوان ژورنال: Algorithmica
سال: 2018
ISSN: 0178-4617,1432-0541
DOI: 10.1007/s00453-018-0432-7