Parameterized String Equations

Laurent Bulteau; Michael R. Fellows; Christian Komusiewicz; Frances Rosamond

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arXiv · 2104.14171

Parameterized String Equations

Laurent Bulteau·Michael R. Fellows·Christian Komusiewicz·Frances Rosamond

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Abstract

We study systems of String Equations where block variables need to be assigned strings so that their concatenation gives a specified target string. We investigate this problem under a multivariate complexity framework, searching for tractable special cases such as systems of equations with few block variables or few equations. Our main results include a polynomial-time algorithm for size-2 equations, and hardness for size-3 equations, as well as hardness for systems of two equations, even with tight constraints on the block variables. We also study a variant where few deletions are allowed in the target string, and give XP algorithms in this setting when the number of block variables is constant.

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BibTeX RIS

Laurent Bulteau, Michael R. Fellows, Christian Komusiewicz, Frances Rosamond. 2021-04-29. Parameterized String Equations. https://arxiv.org/abs/2104.14171

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