A 2.5 approximation algorithm for the multi-via assignment problem

The via assignment problem, whose objective is to minimize the number of via columns used, is known to be NP-hard even when each net includes at most three vias. The authors develop efficient approximation algorithms for solving this problem. An algorithm for the case in which the size of each net is bounded by three is presented, and is then extended to the case in which the nets have arbitrary sizes.<
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