DFA of a string with at least two 0’s and at least two 1’s Last Updated : 31 May, 2022 Comments Improve Suggest changes 18 Likes Like Report Problem - Draw deterministic finite automata (DFA) of a string with at least two 0’s and at least two 1’s. The first thing that come to mind after reading this question us that we count the number of 1's and 0's. Thereafter if they both are at least 2 the string is accepted else not accepted. But we do not have any concept of memory in a DFA so we cannot do it by this method. Input : 1 0 1 1 0 0 Output : Accepted Input : 1 1 1 0 1 Output : Not accepted Approach Used - The first thing we observe is that both 0's and 1's should be at least 2. If any of these is less than 2, then string will not be accepted. In this string will be accepted in only last case where both 0's and 1's will be at least 2. StateCount of 0Count of 1Q000Q101Q20>=2Q310Q411Q51>=2Q6>=20Q7>=21Q8 ACCEPTED>=2>=2 Initially count of both 0 and 1 is zero and we are on state Q0. Step-1: If input is 1 then count of 1 increases to 1. Goto state Q1 If input is 0 then count of 0 increases to 1. Goto state Q3Step-2: If input is 1 then count of 1 increases to 2. Goto state Q2 If input is 0 then count of 0 increases to 1. Goto state Q4Step-3: If input is 1 then count of 1 keeps increasing by 1. Remain in the same state If input is 0 then count of 0 increases to 1. Goto state Q5Step-4: If input is 1 then count of 1 increases to 1. Goto state Q4 If input is 0 then count of 0 increases to 2. Goto state Q6Step-5: If input is 1 then count of 1 increases to 2. Goto state Q5 If input is 0 then count of 0 increases to 2. Goto state Q7Step-6: If input is 1 then count of 1 keeps increasing by 1. Remain in the same state. If input is 0 then count of 0 increases to 2. Goto state Q8Step-7: If input is 1 then count of 1 increases to 1. Goto state Q7 If input is 0 then count of 0 keeps increasing by 1. Remain in the same state.Step-8: If input is 1 then count of 1 increases to 2. Goto state Q8 If input is 0 then count of 0 keeps increasing by 1. Remain in the same state.Step-9: If input is 1 then count of 1 keeps increasing by 1. Remain in the same state. If input is 0 then count of 0 keeps increasing by 1. Remain in the same state. If string is finished then ACCEPTED Create Quiz Comment R RishabhMalik Follow 18 Improve R RishabhMalik Follow 18 Improve Article Tags : Misc GATE CS Theory of Computation Explore Automata _ IntroductionIntroduction to Theory of Computation5 min readChomsky Hierarchy in Theory of Computation2 min readApplications of various Automata4 min readRegular Expression and Finite AutomataIntroduction of Finite Automata3 min readArden's Theorem in Theory of Computation6 min readSolving Automata Using Arden's Theorem6 min readL-graphs and what they represent in TOC4 min readHypothesis (language regularity) and algorithm (L-graph to NFA) in TOC7 min readRegular Expressions, Regular Grammar and Regular Languages7 min readHow to identify if a language is regular or not8 min readDesigning Finite Automata from Regular Expression (Set 1)4 min readStar Height of Regular Expression and Regular Language3 min readGenerating regular expression from Finite Automata3 min readCode Implementation of Deterministic Finite Automata (Set 1)8 min readProgram for Deterministic Finite Automata7 min readDFA for Strings not ending with "THE"12 min readDFA of a string with at least two 0’s and at least two 1’s3 min readDFA for accepting the language L = { anbm | n+m =even }14 min readDFA machines accepting odd number of 0’s or/and even number of 1’s3 min readDFA of a string in which 2nd symbol from RHS is 'a'10 min readUnion Process in DFA4 min readConcatenation Process in DFA3 min readDFA in LEX code which accepts even number of zeros and even number of ones6 min readConversion from NFA to DFA5 min readMinimization of DFA7 min readReversing Deterministic Finite Automata4 min readComplementation process in DFA2 min readKleene's Theorem in TOC | Part-13 min readMealy and Moore Machines in TOC3 min readDifference Between Mealy Machine and Moore Machine4 min readCFGRelationship between grammar and language in Theory of Computation4 min readSimplifying Context Free Grammars6 min readClosure Properties of Context Free Languages11 min readUnion and Intersection of Regular languages with CFL3 min readConverting Context Free Grammar to Chomsky Normal Form5 min readConverting Context Free Grammar to Greibach Normal Form6 min readPumping Lemma in Theory of Computation4 min readCheck if the language is Context Free or Not4 min readAmbiguity in Context free Grammar and Languages3 min readOperator grammar and precedence parser in TOC6 min readContext-sensitive Grammar (CSG) and Language (CSL)2 min readPDA (Pushdown Automata)Introduction of Pushdown Automata5 min readPushdown Automata Acceptance by Final State4 min readConstruct Pushdown Automata for given languages4 min readConstruct Pushdown Automata for all length palindrome6 min readDetailed Study of PushDown Automata3 min readNPDA for accepting the language L = {anbm cn | m,n>=1}2 min readNPDA for accepting the language L = {an bn cm | m,n>=1}2 min readNPDA for accepting the language L = {anbn | n>=1}2 min readNPDA for accepting the language L = {amb2m| m>=1}2 min readNPDA for accepting the language L = {am bn cp dq | m+n=p+q ; 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