Succinct Data Structure for Chordal Graphs with Bounded Vertex Leafage
<|reference_start|>Succinct Data Structure for Chordal Graphs with Bounded Vertex Leafage: We improve the worst-case information theoretic lower bound of Munro and Wu (ISAAC 2018) for $n-$vertex unlabeled chordal graphs when vertex leafage is bounded and leafage is unbounded. The class of unlabeled $k-$vertex leafage chordal graphs that consists of all chordal graphs with vertex leafage at most $k$ and unbounded leafage, denoted $\mathcal{G}_k$, is introduced for the first time. For $k>0$ in $o(n/\log n)$, we obtain a lower bound of $((k-1)n \log n -kn \log k - O(\log n))-$bits on the size of any data structure that encodes a graph in $\mathcal{G}_k$. Further, for every $k-$vertex leafage chordal graph $G$ such that for $k>1$ in $o(n^c), c >0$, we present a $((k-1)n \log n + o(kn \log n))-$bit succinct data structure, constructed using the succinct data structure for path graphs with $kn/2$ vertices. Our data structure supports adjacency query in $O(k \log n)$ time and using additional $2n \log n$ bits, an $O(k^2 d_v \log n + \log^2 n)$ time neighbourhood query where $d_v$ is degree of $v \in V$.<|reference_end|>
@article{balakrishnan2024succinct,
    title={Succinct Data Structure for Chordal Graphs with Bounded Vertex Leafage},
    author={Girish Balakrishnan, Sankardeep Chakraborty, N S Narayanaswamy,
  Kunihiko Sadakane},
    journal={arXiv preprint arXiv:2402.03748},
    year={2024},
    archivePrefix={arXiv},
    eprint={2402.03748},
    primaryClass={cs.DS}
}