Approximations for Aligned Coloring and Spillage Minimization in Interval and Chordal Graphs
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چکیده
We consider the problem of aligned coloring of interval and chordal graphs. These problems have substantial applications to register allocation in compilers and have recently been proven NP-Hard. We provide the first constant approximations: a 4 3 -approximation for interval graphs and a 3 2 -approximation for chordal graphs. We extend our techniques to the problem of minimizing spillage in these graph types.
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تاریخ انتشار 2009