1.A: Let Sigma be {a,b}. Draw a DFA that will accept the set of all strings x in which the last letter of x occurs exactly twice in a row. That is, this DFA should accept bbabbbaa (because there are two a's at the end), and aaabb (two b's), but should not accept aaa (3 a's in a row, and 3 is not exactly 2), nor single letter words such as 'b', nor baba, etc.
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1.A: Let Sigma be {a,b}. Draw a DFA that will accept the set of all strings...
For Σ = {a, b}, construct a DFA that accept the sets consisting of all strings with at least one b and exactly two a's. Note: provide input to thoroughly test the DFA.
(20) Let L be the language over {a,b,c} accepting all strings so that: 1. No b's occur before the first c. 2. No a's occur after the first c. 3. The last symbol of the string is b. 4. Each b that is not the last symbol is immediately followed by at least two c's. 5. There are exactly as many a's as b's. Construct a context-free grammar generating L. You do not need an inductive proof, but you should...
For ∑ = {a, b}, construct a dfa that accepts the set consisting of all strings with at least one b and exactly two a’s
1. Give a context-free grammar for the set BAL of balanced strings of delimiters of three types (), and . For example, (OOis in BAL but [) is not. Give a nondeterministic pushdown automata that recognizes the set of strings in BAL as defined in problem 1 above. Acceptance should be by accept state. 2. Give a context free grammar for the language L where L-(a"b'am I n>-o and there exists k>-o such that m-2*ktn) 3. Give a nondeterministic pushdown...
1. (15) Let L be the language over {a,b,c} accepting all strings so that: 1. No b's occur before the first c. 2. No a's occur after the first c. 3. The last symbol of the string is b. 4. Each b that is not the last symbol is immediately followed by at least two c's. Choose any constructive method you wish, and demonstrate that is regular. You do not need an inductive proof, but you should explain how your...
1. Let L be the language over {a, b, c} accepting all strings so that: 1. No b's occur before the first c. 2. No a's occur after the first c. 3. The last symbol of the string is b. 4. Each b that is not the last symbol is immediately followed by at least two d's. Choose any constructive method you wish, and demonstrate that L is regular. You do not need an inductive proof, but you should explain how your construction accounts for...
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2. 9 marks] Strings. Consider the following definitions on strings Let U be the set of all strings. Let s be a string. The length or size of a string, denoted Is, is the number of characters in s Let s be a string, and ie N such that 0 Si< Is. We write si] to represent the character of s at index i, where indexing starts at 0 (so s(0 is the first character, and s|s -1 is the...
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=(V, En) 5. Let n1 be an integer and define the graph Gn as follows {0,1}", the set of all binary strings of length n. Vn = Two vertices x and y are connected by an edge emu if and only if x and y differs in exactly one position. (a) (4 points) Draw the graph Gn for n = 1,2,3 (b) (4 points) For a general n 2 1, find |Vn and |En (c) (10 points) Prove that for...