PPT-Non-regular languages - The pumping lemma

Regular Languages Regular languages are the languages which are accepted by a Finite Automaton Not all languages are regular NonRegular Languages L 0 a k b k k0 ε is a regular language. Lecture4: Non Regular Languages. Prof. Amos Israeli. Motivate the Pumping Lemma. . Present and demonstrate the . pumping. concept.. Present and prove the . Pumping Lemma. .. Use the pumping lemma to . Class 5: . Non-Regular Languages. Spring 2010. University of Virginia. David Evans. TexPoint fonts used in EMF. . Read the TexPoint manual before you delete this box.: . A. A. A. A. A. A. A. A. A. A. Reading: Chapter 4. 2. Topics. How to prove whether a given language is regular or not?. Closure properties of regular languages. Minimization of DFAs. 3. Some languages are . not . regular. When is a language is regular? . Proving a Language is Not Regular. Dr. Cynthia Lee - UCSD . -. Spring 2011. . Theory of Computation Peer Instruction Lecture Slides by . Dr. Cynthia Lee, UCSD.  are licensed under a . Creative Commons Attribution-. Examples. L. >. = {. a. i. b. j. : . i. > j}. L. >. . is not regular.. . We prove it using the Pumping Lemma.. L. >. = {. a. i. b. j. : . i. > j}. L. >. is not regular.. . Regular Languages. The regular languages are the languages that DFA accept.. Since DFA are equivalent with NFA. ε. , in order to show that L is regular it suffices to construct an NFA. ε. . that recognizes L.. Reading: Chapters 1-4. 2. Test Details. In class, . Wednesday, Feb. 25, 2015. 3:10pm-4pm. Comprehensive. Closed book, closed notes. 3. Syllabus. Formal proofs. Finite Automata. NFA, DFA, . . -NFA. Fall 2017. http://cseweb.ucsd.edu/. classes/fa17/cse105-a/. Today's learning goals . Sipser Ch 1.4. Explain the limits of the class of regular languages. Justify why the Pumping Lemma is true. Apply the Pumping Lemma in proofs of . Fall 2017. http://cseweb.ucsd.edu/classes/fa17/cse105-a/. Today's learning goals . Sipser Ch 1.2, 1.3. Decide whether or not a string is described by a given regular expression. Design a regular expression to describe a given language. some languages are not regular!. Sipser. pages 77 - 82. Are all Languages Regular. We have seen many ways. to specify Regular languages. Are all languages Regular languages?. The answer is No, . H. Theory of Computation Peer Instruction Lecture Slides by . Dr. Cynthia Lee, UCSD.  are licensed under a . Creative Commons Attribution-. NonCommercial. -. ShareAlike. 3.0 . Unported. License. .. 1 Lemma Property for Regular Languages * Josue N. Rivera and Haiping Xu Computer and Information Science Department University of Massachusetts Dartmouth, Dartmouth, MA, USA Email: { josue.n.rivera, h Chuck Cusack. Based on “Introduction to the Theory of Computation”, 3. rd. edition, Michael Sipser. Pumping Lemma for CFLs. If . A. is a CFL, then .  . p. such that for every . s. . A. with |s|. Last time: . - Context free grammars (CFGs) . - Context free languages (CFLs). - Pushdown automata (PDA). - Converting CFGs to PDAs. Today: . (Sipser §2.3, §3.1) . - Proving languages not Context Free.