Automata Theory Questions
A regular expression is a sequence of characters that represents a pattern or a set of strings in automata theory and formal language theory. It is used to describe and define regular languages, which are a type of formal language that can be recognized by a deterministic finite automaton (DFA) or a non-deterministic finite automaton (NFA). Regular expressions consist of a combination of characters and special symbols that represent operations such as concatenation, alternation, and repetition. They provide a concise and flexible way to specify patterns and match strings in various applications, including text processing, pattern matching, and lexical analysis.