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arXiv · 2101.06645

The Complexity of Bicriteria Tree-Depth

Piotr Borowiecki·Dariusz Dereniowski·Dorota Osula
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Abstract

The tree-depth problem can be seen as finding an elimination tree of minimum height for a given input graph $G$. We introduce a bicriteria generalization in which additionally the width of the elimination tree needs to be bounded by some input integer $b$. We are interested in the case when $G$ is the line graph of a tree, proving that the problem is NP-hard and obtaining a polynomial-time additive $2b$-approximation algorithm. This particular class of graphs received significant attention in the past, mainly due to a number of potential applications, e.g. in parallel assembly of modular products, or parallel query processing in relational databases, as well as purely combinatorial applications, including searching in tree-like partial orders (which in turn generalizes binary search on sorted data).

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Piotr Borowiecki, Dariusz Dereniowski, Dorota Osula. 2021-01-17. The Complexity of Bicriteria Tree-Depth. https://arxiv.org/abs/2101.06645

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