Recent questions and answers in Theory of Computation

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Give an $NFA$ recognizing the language $(01 ∪ 001 ∪ 010)^{*}.$Convert this $NFA$ to an equivalent $DFA.$ Give only the portion of the $DFA$ that is reachable from the start state.
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Give a counterexample to show that the following construction fails to prove $\text{Theorem 1.49,}$ the closure of the class of regular languages under the star operation$.$ ... $N$ does not recognize the star of $N_{1}^{'s}$ language.
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Show that if $M$ is a $DFA$ that recognizes language $B,$ swapping the accept and not accept states in $M$ yields a new $DFA$ recognizing the ... of languages recognized by $NFA's$ closed under complement$?$ Explain your answer$.$
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Let $F$ be the language of all strings over $\{0,1\}$ that do not contain a pair of $1's$ that are separated by an odd number of symbols. Give the state ... helpful first to find a $4$-state $\text{NFA}$ for the complement of $F.)$
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The formal description of a $\text{DFA}$ $\text{M}$ is $({q1, q2, q3, q4, q5}, {u, d}, δ, q3, {q3}),$ where $\text{δ}$ is given by the following table. Give the state diagram of this machine.
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The following are the state diagrams of two $\text{DFAs,}$ $\text{M1}$, and $\text{M2.}$ Answer the following questions about each of these machines.What ... accept the string $\text{aabb?}$Does the machine accept the string $\epsilon?$
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Find the error in the following proof that $2 = 1.$Consider the equation $a = b.$ Multiply both sides by a to obtain $a^{2} = ab.$ Subtract $b^{2}$ from both sides to ... $a$ and $b$ equal $1,$ which shows that $2 = 1.$
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Consider the undirected graph G= (V, E) where V , the set of nodes, is {1, 2, 3, 4} and E, the set of edges, is {{1, 2}, {2, 3}, {1, 3}, {2 ... . What are the degrees of each node? Indicate a path from node 3 to node 4 on your drawing of G.
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For each part, give a relation that satisfies the condition.Reflexive and symmetric but not transitiveReflexive and transitive but not symmetricSymmetric and transitive but not reflexive
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If A has a elements and B has b elements, how many elements are in A × B? Explain your answer.
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Write formal descriptions of the following sets.a. The set containing the numbers 1, 10, and 100b. The set containing all integers that are greater than 5c ... abae. The set containing the empty stringf. The set containing nothing at all
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Examine the following formal descriptions of sets so that you understand which members they contain. Write a short informal English description of each set.a. {1, 3, 5, 7, . . . }b ... the reverse of w}f. {n| n is an integer and n = n + 1}
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Write Regular expression for the set of string over alphabets {a, b} starting with b and ending with odd number of a’s or even number of b’s.
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construct a minimal DFA for the regular language L= {W | w contain 'a' in every odd position, w∈{a,b}* }
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DFA
Identify language accepted by following dfa. A. L = {a^n b^m | n,m >= 1} B. L = {a^n b^m | n >= 1, m >= 0} C. L = {a^n b^m | n,m >= 0} D. None
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Let $L_{1}$ be the language represented by the regular expression $b^{*} a b^{*}\left(a b^{*} a b^{*}\right)^{*}$ ... of string $w$. The number of strings in $L_{2}$ which are also in $L_{1}$ is _________.
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Let $M = (K, Σ, Г, Δ, s, F)$ be a pushdown automaton, where$K = (s, f), F = \{f\}, \Sigma = \{a, b\}, Г = \{a\}$ ... , (f, \epsilon))\}$.Which one of the following strings is not a member of $L(M)$?$aaa$aabab$baaba$bab$
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A general query,If Regular expression (a+b)* covers the all possible languages over $\sum$= {a,b} then, why we need other type of languages?Are they ... I found these two reasons on internet and nothing else is there any other reasons here?
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Captioncreate a DFA for language L={a^n b^m | n=(m%3) } 
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TOC
Number of states in a DFA that accepts string over the alphabet {0,1} where words start and end with a 1, have even length and every 0 is immediately followed by atleast a 1.
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Let $\Sigma$ be the set of all bijections from $\{1, \dots , 5\}$ to $\{1, \dots , 5 \}$, where $id$ ... $L$ is _______
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The following diagram represents a finite state machine which takes as input a binary number from the least significant bit. Which of the ... complement of the input numberIt increments the input numberit decrements the input number
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Draw a DFA and Transition table for the regular expression (a|b)*abb
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Let $\text{M}$ be the $5$-state $\text{NFA}$ with $\epsilon$ ... {*}\right)(11)^{*}$0^{+}+1(11)^{*}+0(11)^{*}$
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Which one of the following regular expressions is equivalent to the language accepted by the $\text{DFA}$ given below?$0^{*} 1\left(0+10^{*} 1\right)^{*}$0^{*}\left(10^{*} 11\ ... )^{*} 0^{*}$0\left(1+0^{*} 10^{*} 1\right)^{*} 0^{*}$
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Let M1 = (Q1, {q1}, ∆1, F1), where ∆1 ⊆ Q1 (Σ ∪ {ϵ}) Q1, be a non-deterministic finite automaton (NFA) accepting a language L1 ⊆ {0, 1} ∗ . Let ϵ denote ... = ϵ and p ′ = q1) Prove or disprove: The language L2 accepted by M2 is L ∗ 1 .
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Let M1 = (Q1, {q1}, ∆1, F1), where ∆1 ⊆ Q1 (Σ ∪ {ϵ}) Q1, be a non-deterministic finite automaton (NFA) accepting a language L1 ⊆ {0, 1} ∗ . Let ϵ ... F1 and a = ϵ and p ′ = q1) Prove or disprove: The language L2 accepted by M2 is L*
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Design a DFA (Deterministic Finite Automaton) that recognizes the language L defined follows: L= {w -> {a, b}* | every a in w is immediately followed by bb}
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Which f the following statements is FALSE?The intersection of a regular language and a context-free language is context=freeThe intersection of a regular ... -free languages is context-freeThe union of two regular languages is regular
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Can
Can $\Sigma^{*}$ be called DCFL? If yes, what would the state transition diagram of its PDA look like?
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Which of the following regular expression represent the set of all the strings not containing $100$ as a substring ?$0^*(1^*0)^*$0^*1010^*$0^*1^*01^*$0^*(10+1)^*$
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Consider the following languages:$L_{1} = \{ ww | w \in \{a,b\}^{\ast} \}$ ... $L_{2} \cap L_{3}$ all are context-free.Neither $L_{1}$ nor its complement is context-free.
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Let r = a(a + b)*, S = aa*b and t = a* b be three regular expressions. Consider the following:Which one of them is correct ?
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Below you see the transition table of a finite state automaton. The initial state is $0;$ the final state is $4.$ $\emptyset$ denotes the fail state, where no successful transition ... mathrm{abbb}^+\mathrm{c}^+\mathrm{c}$a b^* b b(c c)^+$
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How a^i b^j | i !=(2j+1) is dcfl?
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Consider the context-free grammer $G$ below. There $S$ is the starting non terminal symbol, while $a$ and $b$ are terminal symbols.$S \rightarrow aaSb | T$T \ ... $aabbaabb$ does not$aaabb$ belongs to $L(G)$ but $aaaaabbb$ does not
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Which of the following strings are a member of the language described by the regular expression $\left(a^* {b} {a}^* b a^* b {a}^*\right)^*$b b b b$bbaaabb$bbaaabbbabb$b b a b b b a b$
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