Pattern of Strings

Pattern Searching

Last Updated : 05 Dec, 2024

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Pattern searching algorithms are essential tools in computer science and data processing. These algorithms are designed to efficiently find a particular pattern within a larger set of data.

Pattern-Searching — Patten Searching

Important Pattern Searching Algorithms:

Naive String Matching : A Simple Algorithm that works in O(m x n) time where m is the length of the pattern and n is the length of the text.
Knuth-Morris-Pratt (KMP) Algorithm It preprocesses pattern and works in O(m + n) Time.
Rabin-Karp Algorithm : It uses hashing to compare the pattern with the text. It works in O(m x n) Time in worst case,
Aho-Corasick Algorithm : A deterministic finite automaton (DFA) based algorithm and works in O(m + n) time.

Learn Basics of Pattern Searching:

Standard Pattern Searching Algorithms:

Practice Problems on Pattern Searching:

Applications of Pattern Searching

Pattern searching algorithms have numerous applications, including:

Text Processing: Searching for keywords in a document, finding and replacing text, spell checking, and plagiarism detection.
Information Retrieval: Finding relevant documents in a database, web search, and data mining.
Bioinformatics: Searching for DNA sequences in a genome, protein analysis, and gene expression analysis.
Network Security: Detecting malicious patterns in network traffic, intrusion detection, and malware analysis.
Data Mining: Identifying patterns in large datasets, customer segmentation, and fraud detection.

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