SOFSEM on

SOFSEM2026

Thu, 01 Jan 2026 00:00:00 +0000

Given a set of results from range minimum queries (RMQs), our task is to construct a sequence that is consistent with the results of the queries. We study two types of RMQs: a value-based RMQ returns the minimum value and an index-based RMQ returns the index of the…

SOFSEM2025

Mon, 20 Jan 2025 00:00:00 +0000

This paper is concerned with learning some context-free languages (cfls) over infinite alphabets from membership and equivalence queries. Argyros and D’Antoni (2018) proposed a query learning algorithm for regular languages over infinite alphabets using…

桂敬史くん（博士3年）がSOFSEM2015でBest Student Poster Awardを受賞

Thu, 29 Jan 2015 00:00:00 +0000

博士課程後期3年の桂敬史くんが2015年1月24日-29日にチェコで開催された国際会議SOFSEM 2015 （41st International Conference on Current Trends in Theory and Practice of Computer Science）において，Best Student Poster Awardを受賞しました．

SOFSEM2015

Mon, 26 Jan 2015 00:00:00 +0000

A multi-set of $N$ strings of length $n$ is called a multi-track string. The permuted pattern matching is the problem that given two multi-track strings $T = { t_1, \ldots, t_N }$ of length $n$ and $P = {p_1, \ldots, p_{N}}$ of length $m$, outputs all positions $i$ such that ${p_1 \ldots, p_N} = {t_1[i : i + m_1], \ldots, t_N[i:i+m_1]}$. We propose two newi ndexing structures for multi-track stings. One is a time-efficient structure for $T$ that needs $O(nN)$ space and enables us to solve the problem in $O(m^2 N+occ)$ time, where $occ$ is the number of occurrences of the pattern $P$ in the text $T$. The other is memory-e cient, it requires only $O(n)$ space, whereas the matching consumes $O(m^2 N^2 + occ)$ time. We show that both of them can be constructed in $O(nN)$ time.

SOFSEM 2015

Sun, 25 Jan 2015 00:00:00 +0000

チェコで開催された国際会議SOFSEM2015においてD3の桂敬史君がポスター発表を行いました。（1月24日～29日）