Abstract
Let T be an edge-weighted tree. A p-core of T is a set of p mutually disjoint paths in T that minimizes the sum of the distances of all vertices in T from any of the p paths, where p≥1 is an integer. Let n be the number of vertices in T. In this paper, an O(n) time algorithm is proposed for the case p=2. Applying our 2-core algorithm as a procedure, we also show that the p-core problem can be solved in O(n p-1) time for any constant p≥2.
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Wang, BF., Lin, JJ. (2000). Finding a Two-Core of a Tree in Linear Time. In: Goos, G., Hartmanis, J., van Leeuwen, J., Lee, D.T., Teng, SH. (eds) Algorithms and Computation. ISAAC 2000. Lecture Notes in Computer Science, vol 1969. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-40996-3_40
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DOI: https://doi.org/10.1007/3-540-40996-3_40
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