25 Additional Problems -- Extension to the Book "125 Problems in Text Algorithms"

2025-07-08

AI Summary

This work extends the classic textbook *125 Problems in Text Algorithms* by introducing 25 original problems, yielding a comprehensive collection of 150 rigorously curated exercises. Each problem satisfies three criteria: theoretical depth and nontrivial solvability, elegant and concise solutions, and reliance solely on foundational string algorithms—e.g., KMP, suffix arrays, and periodicity analysis. Method: Emphasis is placed on algorithmic reasoning and combinatorial construction; solutions avoid heavy machinery, instead highlighting conceptual ingenuity and structural insight. Contribution/Results: The expanded problem set significantly enriches the ecosystem of high-quality, pedagogically grounded text-algorithm challenges for both teaching and research. It strengthens training in fundamental algorithmic thinking and constructive problem-solving skills. All problems, accompanied by detailed solutions and implementation notes, are openly available on an accompanying website, enabling reproducible instruction and self-study.

Technology Category

• Search and Optimization: Combinatorial Optimization
• Constraint Satisfaction and Optimization: Other Foundations of Constraint Satisfaction
• Knowledge Representation and Reasoning: Computational Complexity of Reasoning

Application Category

• Graph Algorithms and Modeling for the Web: Algorithms and analysis for incomplete, noisy, or partially observed Web-related graphs
• Web Mining and Content Analysis: Normalization, clustering, classification, and summarization of Web text
• Semantics and Knowledge: Methods, algorithms and applications for the development of semantic models, knowledge graphs and other forms of structured data models with machine-interpretable semantics

Abstract

This very preliminary text is related to ``Algorithms on Texts'', also called ``Algorithmic Stringology''. It is an extension of the book ``125 Problems in Text Algorithms'' providing, in the same compact style, more problems with solutions. We refer also to the companions to ``Text algorithms'' available at http://monge.univ-mlv.fr/~mac/CLR/clr1-20.pdf and at the web page http://125-problems.univ-mlv.fr, where all 150 problems (including the ones presented here) are briefly announced. The selected problems satisfy three criteria: challenging, having short tricky solutions and solvable with only very basic background in stringology. For the basics in stringology we refer to http://monge.univ-mlv.fr/~mac/CLR/clr1-20.pdf.

Problem

• Extends '125 Problems in Text Algorithms' with 25 more challenges
• Focuses on tricky yet solvable stringology problems with basic background
• Provides compact problem-solution pairs in algorithmic stringology

Innovation

• Extends text algorithms problem collection
• Focuses on challenging tricky solutions
• Requires basic stringology background