# Parallel Duel-and-Sweep Algorithm for the Order-Preserving Pattern Matching

• Davaajav Jargalsaikhan
• Diptarama Hendrian
• Ryo Yoshinaka
• Ayumi Shinohara
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 12011)

## Abstract

Given a text and a pattern over an alphabet, the classic exact matching problem searches for all occurrences of pattern P in text T. Unlike the exact matching problem, order-preserving pattern matching considers the relative order of elements, rather than their exact values. In this paper, we propose the first parallel algorithm for the OPPM problem. Our algorithm is based on the “duel-and-sweep” algorithm. For a pattern of length m and a text of length n, our algorithm runs in $$O(\log ^ 3 m)$$ time and $$O(n \log ^ 3 m)$$ work on the Priority CRCW PRAM.

## Keywords

String matching Order-preserving pattern matching Parallel algorithm

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© Springer Nature Switzerland AG 2020

## Authors and Affiliations

• Davaajav Jargalsaikhan
• 1
Email author
• Diptarama Hendrian
• 1
• Ryo Yoshinaka
• 1
• Ayumi Shinohara
• 1
1. 1.Graduate School of Information SciencesTohoku UniversitySendaiJapan