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An example of a rule is

[[latex2($A \rarrow aBa$)]]
[[latex2($B \rarrow \epsilon$)]]

Context Free Grammar

Def: For every ContextFreeLanguage there is a ContextFreeGrammar that generates it and a PushDownAutomata that recognizes it.

A context-free grammar is a 4-tuple latex2($(V,\Sigma,R,S)$), where

  1. Element latex2($V$) is a finite set called the variables,

  2. Element latex2($\Sigma$) is a finite set, disjoint from latex2($V$), called the terminals,

  3. Element latex2($R$) is a finite set of rules, with each rule being a variable and a string of variables and terminals, and

  4. Element latex2($S \in V$) is the start variable

An example of a rule is

latex2($A \rarrow aBa$) latex2($B \rarrow \epsilon$)

ContexFreeGrammar (last edited 2020-01-26 17:53:59 by scot)