1 citations · 1 across the 10 of their papers we have counts for
13 papers
Forcing a unique minimum spanning tree and a unique shortest path
Tatsuya Gima, Andreas Grigorjew, Yasuaki Kobayashi +7
A forcing set in a combinatorial problem is a set of elements such that there is a unique solution that contains all the elements in . An anti-forcing set is the symmetric c…
Broadcasting under Structural Restrictions
Yudai Egami, Tatsuya Gima, Tesshu Hanaka +7
In the Telephone Broadcast problem we are given a graph with a designated source vertex . Our goal is to transmit a message, which is initially known only to ,…
Basis sequence reconfiguration in the union of matroids
Tesshu Hanaka, Yuni Iwamasa, Yasuaki Kobayashi +2
Given a graph and two spanning trees and in , Spanning Tree Reconfiguration asks whether there is a step-by-step transformation from to such that all inter…
Theoretical Aspects of Generating Instances with Unique Solutions: Pre-assignment Models for Unique Vertex Cover
Takashi Horiyama, Yasuaki Kobayashi, Hirotaka Ono +2
The uniqueness of an optimal solution to a combinatorial optimization problem attracts many fields of researchers' attention because it has a wide range of applications, it is rela…
On the complexity of list -packing for sparse graph classes
Tatsuya Gima, Tesshu Hanaka, Yasuaki Kobayashi +5
The problem of packing as many subgraphs isomorphic to as possible in a graph for a class of graphs is well studied in the literature. Both vertex-d…
Structural Parameterizations of Vertex Integrity
Tatsuya Gima, Tesshu Hanaka, Yasuaki Kobayashi +3
The graph parameter vertex integrity measures how vulnerable a graph is to a removal of a small number of vertices. More precisely, a graph with small vertex integrity admits a sma…
Finding a reconfiguration sequence between longest increasing subsequences
Yuuki Aoike, Masashi Kiyomi, Yasuaki Kobayashi +1
In this note, we consider the problem of finding a step-by-step transformation between two longest increasing subsequences in a sequence, namely Longest Increasing Subsequence Reco…
Finding a Minimum Spanning Tree with a Small Non-Terminal Set
Tesshu Hanaka, Yasuaki Kobayashi
In this paper, we study the problem of finding a minimum weight spanning tree that contains each vertex in a given subset of vertices as an internal vertex. This probl…
Reconfiguration of Time-Respecting Arborescences
Takehiro Ito, Yuni Iwamasa, Naoyuki Kamiyama +4
An arborescence, which is a directed analogue of a spanning tree in an undirected graph, is one of the most fundamental combinatorial objects in a digraph. In this paper, we study…
Frameworks to Design Approximation Algorithms for Finding Diverse Solutions in Combinatorial Problems
Tesshu Hanaka, Masashi Kiyomi, Yasuaki Kobayashi +4
Finding a \emph{single} best solution is the most common objective in combinatorial optimization problems. However, such a single solution may not be applicable to real-world probl…
Reconfiguration of Regular Induced Subgraphs
Hiroshi Eto, Takehiro Ito, Yasuaki Kobayashi +2
We study the problem of checking the existence of a step-by-step transformation of -regular induced subgraphs in a graph, where and each step in the transformation mus…
Parameterized Complexity of -Path Packing
Rémy Belmonte, Tesshu Hanaka, Masaaki Kanzaki +6
Given a graph , , and integers and , the \textsc{-Path Packing} problem asks to find vertex-disjoint paths of length that h…
Subgraph Isomorphism on Graph Classes that Exclude a Substructure
Hans L. Bodlaender, Tesshu Hanaka, Yasuaki Kobayashi +4
We study Subgraph Isomorphism on graph classes defined by a fixed forbidden graph. Although there are several ways for forbidding a graph, we observe that it is reasonable to focus…