Finding separator cuts in planar graphs within twice the optimal

Building on the works of S.B. Rao (1987, 1992) and J.K. Park and C.A. Phillips (1993), we present a factor 2 approximation algorithm for the problem of finding a minimum cost b-balanced cut in planar graphs, for b/spl les/1/3, if the vertex weights are given in unary (using scaling, a psuedo-approximation algorithm is also presented for the case of binary vertex weights). This problem is of considerable practical significance, especially in VLSI design.<
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