Computation, Computers, and ProgramsCourse Introduction

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CS20a Computation, Computers, Programs

• Instructor Jason Hickey
• Email jyh_at_cs.caltech.edu
• Office hours TR 10-11am
• TAs
• Nathan Gray (n8gray_at_cs.caltech.edu)
• Brian Aydemir (emre_at_cs.caltech.edu)
• Jason Frantz (frantz_at_its.caltech.edu)
• Robert Li (robertli_at_its.caltech.edu)

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Outline

• Alphabets and strings
• DFAs

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Decision problems
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Alphabets
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Strings
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Notation
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Grouping
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Wolves, Goats, and cabbages
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Determistic Finite Automata
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Transition diagrams
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A finite automaton
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Extending the transition function
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Definitions and conventions
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Some properties of regular languages
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Complement is regular
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Intersection is regular
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Products
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Verifying the product machine
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Equational proofs
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Main lemma
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Induction step
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Product theorem
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Regular expressions
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Definition of regular expressions
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Examples of regular expressions