Test_2_Study_Guide - variables o Σ is a finite set...

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Pumping Lemma for Regular Expressions For each ≥ , i 0 xyiz A > y 0 xy p Pushdown Automaton (PDA) A pushdown automaton is a 6-tuple ( , , , , , ) Q Σ Γ δ q0 F , where , , , Q Σ Γ and F are all finite sets, and o Q is the set of states o Σ is the input alphabet o Γ is the stack alphabet o : × × → ( × ) δ Q Σε Γε P Q Γε is the transition function o q0 Q is the start state o F Q is the set of accept states o o Context-Free Grammar A context-free grammar is a 4-tuple ( , , , ) V Σ R S , where o V is a finite set called the
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Unformatted text preview: variables o Σ is a finite set, disjoint from V, called the terminals o R is a finite set of rules , with each rule being a variable and a string of variables and terminals o ∈ S V is the start variable • Ambiguity : If a grammar generates the same string in several different ways, we say that the string is derived ambiguously in that grammar. o o Pumping Lemma for Context-Free Languages o for each ≥ , ∈ i 0 uvixyiz A o > vy 0 o ≤ vxy p o o o...
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This note was uploaded on 04/28/2009 for the course CSC 333 taught by Professor Samatova during the Spring '08 term at N.C. State.

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