PPT-Chapter 7 PUSHDOWN AUTOMATA

Chapter 7 PUSHDOWN AUTOMATA Learning Objectives At the conclusion of the chapter the student will be able to Describe the components of a nondeterministic pushdown automaton State whether an input string is accepted by a. of auxiliary . storage. Gennaro. . Parlato. . (University of Southampton, UK). Joint work: . P. . Madhusudan. – UIUC, USA . . . Automata with aux storage. Turing machines = finite automata + 1 infinite tape. THEORY. II B. Questions Answers(DFA-NFA) . Dept. of Computer Science & IT, FUUAST Automata Theory . 2. Automata Theory II B. For .  = {a, b} construct DFA that accepts all strings with exactly one ‘a’ .. THEORY. II. 1. . Defs. .. . a) Finite Automaton:. A Finite Automaton ( FA ) has finite set of ‘states’ ( Q={q. 0,. q. 1,. q. 2,. ….. ) and its ‘control’ moves from state to state in response to external ‘inputs’(. THEORY. I. Introduction. What is Automata. Automaton and types of automata. History, Turing Machine. Why study Automata Theory. e) Applications & Uses. Dept. of Computer Science & IT, FUUAST Automata Theory . THEORY. VII. Dept. of Computer Science & IT, FUUAST Automata Theory . 2. Automata Theory VII. Properties of Context-Free Languages. Dept. of Computer Science & IT, FUUAST Automata Theory . THEORY. V. Dept. of Computer Science & IT, FUUAST Automata Theory . 2. Automata Theory V. Context-Free Grammars. and . Languages. A . Reading: Chapter 1. 2. What is Automata Theory?. Study of abstract computing devices, or “machines”. Automaton = an abstract computing device. Note:. A “device” need not even be a physical hardware!. 29-September-2011. Modeling Temporal Behavior of Component. Component behaves with Environment. Traditional (pessimistic) approach. Environment is free to behave as it wants to. Two components are compatible if . Sambhav. . Jain. IIIT Hyderabad. Think !!!. How to store a dictionary in computer?. How to search for an entry in that dictionary?. Say you have each word length exactly equal to 10 characters and can take any letter from ‘a-z’. . Characterization. of. Context-Free. . Trace. . Languages. Benedek Nagy. Friedrich Otto. Department. of Computer Science . Fachbereich. . Elektrotechnik. /. Informatik. Faculty. of . Pierre Bourhis . CNRS . CRIStAL. , Equipe LINKS. Joint . works. . with. . M.Benedikt. , . M.Krötzsch. , S. Rudolph, P. Senellart, M. Van Den Boom. 1. Querying a database . Database : a labelled graph or hypergraph. Reading: Chapter 6. 2. PDA - the automata for CFLs. What is?. FA to Reg Lang, PDA is to CFL. PDA == [. . . . -NFA + “a stack” ]. Why a stack?. . -NFA. A stack filled with “stack symbols”. 2. Finite Automaton (FA). Informally, a state diagram that comprehensively captures all possible states and transitions that a machine can take while responding to a stream or sequence of input symbols. Chapter 7 PUSHDOWN AUTOMATA Learning Objectives At the conclusion of the chapter, the student will be able to: Describe the components of a nondeterministic pushdown automaton State whether an input string is accepted by a