English

$\{s,t\}$-Separating Principal Partition Sequence of Submodular Functions

Data Structures and Algorithms 2026-02-25 v3

Abstract

Narayanan showed the existence of the principal partition sequence of a submodular function, a structure with numerous applications in areas such as clustering, fast algorithms, and approximation algorithms. In this work, motivated by two applications, we develop a theory of {s,t}\{s,t\}-separating principal partition sequence of a submodular function. We define this sequence, show its existence, and design a polynomial-time algorithm to construct it. We show two applications: (1) approximation algorithm for the {s,t}\{s,t\}-separating submodular kk-partitioning problem for monotone and posimodular functions and (2) polynomial-time algorithm for the hypergraph orientation problem of finding an orientation that simultaneously has strong connectivity at least kk and (s,t)(s,t)-connectivity at least \ell.

Keywords

Cite

@article{arxiv.2510.25664,
  title  = {$\{s,t\}$-Separating Principal Partition Sequence of Submodular Functions},
  author = {Kristóf Bérczi and Karthekeyan Chandrasekaran and Tamás Király and Daniel P. Szabo},
  journal= {arXiv preprint arXiv:2510.25664},
  year   = {2026}
}
R2 v1 2026-07-01T07:12:15.776Z