18-REGULAR EXPRESSIONS IN AUTOMATA THEORY || REGULAR EXPRESSION WITH EXAMPLE || TOC

A Regular Expression can be recursively defined as follows − ε is a Regular Expression indicates the language containing an empty string. (L (ε) = {ε}) φ is a Regular Expression denoting an empty language. (L (φ) = { }) x is a Regular Expression where L = {x} If X is a Regular Expression denoting the language L(X) and Y is a Regular Expression denoting the language L(Y), then X + Y is a Regular Expression corresponding to the language L(X) ∪ L(Y) where L(X+Y) = L(X) ∪ L(Y). X . Y is a Regular Expression corresponding to the language L(X) . L(Y) where L(X.Y) = L(X) . L(Y) R* is a Regular Expression corresponding to the language L(R*)where L(R*) = (L(R))* If we apply any of the rules several times from 1 to 5, they are Regular Expressions. ---------------------------------------------------------------------------------------------------------------- AUTOMATA THEORY || THEORY OF COMPUTATION    • 01-INTRODUCTION TO AUTOMATA THEORY AND ITS...   COMPILER DESIGN    • INTRODUCTION TO COMPILERS IN COMPILER DESI...   DATABASE MANAGEMENT SYSTEM    • DATABASE MANAGEMENT SYSTEM   DATA STRUCTURES    • DS_1-Introduction to Data Structures | Mus...   JAVA PROGRAMMING    • Core Java Full Course for Beginners 🚀 | Le...   R PROGRAMMING https://studio.youtube.com/playlist/P... HTML TUTORIALS WITH IMPLEMENTATION || LEARN HTML IN 4 HOURS    • Learn HTML in 4 Hours 🔥 Full Tutorial with...   LEARN CSS IN 3 HOURS || CASCADING STYLE SHEETS FOR BEGINNERS    • Learn CSS with practical explanation in 3 ...   JAVA SCRIPT FOR BEGINNERS IN 7 HOURS || LEARN JAVA SCRIPT IN 7 HOURS || JAVA SCRIPT    • Learn JavaScript in 7 Hours 🕖 | Complete J...   XML (eXtensible Markup Language)    • XML (eXtensible Markup Language)   OPERATING SYSTEM    • OPERATING SYSTEM   ETHICAL HACKING    • Video   VI EDITOR BASICS IN LINUX / UNIX || LEARN VI EDITOR COMMANDS || LINUX || UNIX    • VI EDITOR BASICS IN LINUX / UNIX || LEARN ...   HOW TO DOWNLOAD & INSTALL MySQL IN WINDOWS 10    • HOW TO DOWNLOAD & INSTALL MySQL IN WINDOWS 10   PYTHON PROGRAMS    • PYTHON PROGRAMS   C PROGRAMMING    • 01 - VARIABLES & CONSTANTS in C PROGRAMMING   CORE JAVA TUTORIAL FOR BEGINNERS || LEARN CORE JAVA IN 15 HOURS || JAVA TUTORIALS FOR BEGINNERS    • Core Java Full Course for Beginners 🚀 | Le...   PYTHON TUTORIALS FOR BEGINNERS (తెలుగు లో)    • తెలుగులో Python నేర్చుకోండి | Learn Python...   PYTHON OOPS - MODULES - EXCEPTION HANDLING (తెలుగు లో)    • Python OOPs, Modules & Exception Handling ...   PYTHON NUMPY TUTORIAL IN TELUGU (తెలుగు లో) || COMPLETE NUMPY TUTORIALS IN TELUGU    • Python NumPy Full Tutorial in Telugu (తెలు...   PYTHON PANDAS TUTORIAL IN TELUGU (తెలుగు లో) || COMPLETE PANDAS TUTORIALS IN TELUGU || DATA SCIENCE    • Python Pandas Full Tutorial in Telugu (తెల...   MATPLOTLIB LIBRARY - PYTHON PROGRAMMING (ENGLISH)    • MATPLOTLIB LIBRARY - PYTHON PROGRAMMING   PYTHON DATABASE CONNECTIVITY - MYSQL & MS-EXCEL    • PYTHON DATABASE CONNECTIVITY - MYSQL & MS-...   DATA STRUCTURES USING PYTHON (ENGLISH)    • DATA STRUCTURES USING PYTHON   ---------------------------------------------------------------------------------------------- Instagram :   / sundeepsaradhikanthety