The Maximum Integer Multiterminal Flow Problem
Abstract
Given an edge-capacitated graph and kterminal vertices, the maximum integer multiterminal flow problem (MaxIMTF) is to route the maximum number of flow units between the terminals. For directed graphs, we introduce a new parameter k L ≤ k and prove that MaxIMTF is \(\mathcal{NP}\)-hard when k = k L = 2 and when k L = 1 and k = 3, and polynomial-time solvable when k L = 0 and when k L = 1 and k = 2. We also give an 2 log2 (k L + 2)-approximation algorithm for the general case. For undirected graphs, we give a family of valid inequalities for MaxIMTF that has several interesting consequences, and show a correspondence with valid inequalities known for MaxIMTF and for the associated minimum multiterminal cut problem.
Keywords
Approximation Algorithm Undirected Graph Valid Inequality Terminal Vertex Maximum IntegerPreview
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