Girish Balakrishnan

dblp:163/1404 · DBLP profile ↗
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2ranked-venue papers in the field
2as first author
2since 2021 · last 2024
—ORCID · none

Domains — venue-derived; a paper can count in several

Big Data, Cloud & Distributed Data Systems · 2 (2 first)
YearPublicationVenuePosition
2024 Succinct Data Structure for Graphs with d-Dimensional t-Representation
abstract
Erdős and West (Discrete Mathematics’85) considered the class of n vertex intersection graphs which have a d-dimensional t-representation (also called a t,d −intersection representation), that is, each vertex of a graph in the class has an associated set consisting of at most t d -dimensional axis-parallel boxes. In particular, for a graph G and for each d ≥ 1, they consider i d ( G ) to be the minimum t for which G has such a representation. For fixed t and d , they consider the class of n vertex labeled graphs for which i d ( G ) ≤ t , and prove an upper bound of $\left( {2nt + \frac{1}{2}} \right)d\log n - \left( {n - \frac{1}{2}} \right)d\log (4\pi t)$ on the logarithm of size of the class. In this work, for fixed t and d we consider the class of n vertex unlabeled graphs which have a d -dimensional t -representation, denoted by ${\mathcal{G}_{t,d}}$ . We address the problem of designing a succinct data structure for the class ${\mathcal{G}_{t,d}}$ in an attempt to generalize the relatively recent results on succinct data structures for interval graphs (Algorithmica’21). Let ${\mathcal{G}_t}{\text{and}}{\mathcal{G}_d}$ be the class of graphs with bounded interval number and bounded boxicity obtained by setting d = 1 and t = 1 in ${\mathcal{G}_{t,d}}$ , respectively. We have the following results:
Girish Balakrishnan, Sankardeep Chakraborty, Seungbum Jo, N. S. Narayanaswamy, Kunihiko Sadakane
DCC1
2022 Succinct Data Structure for Path Graphs
abstract
We consider the problem of designing space-efficient data structures for unlabelled path graphs with$n$vertices while supporting basic navigational queries such as degree, adjacency, and neighborhood queries efficiently. We provide two solutions for this problem. Our first data structure is succinct and occupies$n\log n+o(n\log n)$bits while answering adjacency query in$O(\log n)$time, and neighborhood and degree queries in$O(d\log^{2}n)$time where$d$is the degree of the queried vertex. Our second data structure answers all these queries faster at the expense of slightly more space. More specifically, it consumes$O(n\log^{2}n)$bits while answering adjacency and degree queries in constant time and neighborhood query in$O(d\log n)$time. Central to our data structures is the usage of the classical heavy path decomposition, followed by a careful bookkeeping using an orthogonal range search data structure among others, which may be of independent interest for designing succinct data structures for other graphs.
Girish Balakrishnan, N. S. Narayanaswamy, Sankardeep Chakraborty, Kunihiko Sadakane
DCC1