[Modules]
[Syllabus]
Module #2b: Properties of Context-Free Languages
Objectives
- Create equivalent CFG's:
- with a nonrecursive start
- without (most) lambda (epsilon) productions
- without useless symbols
- without unit (aka singleton) productions (aka chain
rules)
- Convert a grammar to Chomsky Normal Form
- Define and occasionally convert grammars to Greibach
Normal Form
- Define closure properties for CFL's
- Define decision properties for CFL's
Topics
- Elimination of epsilon productions
- Elimination of unit rules
- Elimination of useless symbols
- Chomsky Normal Form
- Greibach Normal Form
- Closure Properties of CFL's
Background Material
0. Text
1. Wikepedia:
Context-Free
Grammars
2. Grahne Text Slides: Pages
225-end
3. Busch, Shiri & Grahne:
[PDF]
Simplification of CFG's
4. Busch, Shiri & Grahne:
[PDF]
Closure Properties
5. Video of Grammatical Transformations
[vPOD]
6. Video of
Chomsky Normal Form
[vPOD]
Old Homeworks
Homework Summer 2006
[PDF]
Homework
Solutions Summer 2006
[DOC]
[PDF]
Homework
This homework is in the next module, Module 3