Recent questions tagged regular-expression

Let $G$ have start symbol $q_0$ and productions :$$\begin{aligned}q_0 &\to \epsilon \mid abq_0 \mid cq_1\\q_1 &\to ab\end{aligned}$$Which regular expression denotes $L(G)...

Let $P,Q$ and $R$ be regular expressions such that the number of strings generated by $P$ is $p$, $Q$ is $q$ and $R$ is $r$. What is the number of strings generated by th...

Select the equivalent regular expression for the given $\epsilon$-NFA.$(01)^*1(01)$  $(0+1)^*1(0+1)$  $((0+1)^*+1)(0+1)$  $(01)^*+1+(01)$

$(1(0+1)^*1)^*$ denotes all strings that start and end with $1$.True False

Let $\mathrm{P}$ and $\mathrm{Q}$ be two regular expressions over $\sum$. If $\mathrm{P}$ does not contain $\epsilon$, then the following equation in $\mathrm{R}$ namely,...

If $r_{1}$ and $r_{2}$ are regular expressions, then which of the following are correct.$\mathrm{L}\left(\mathrm{r}_{1}+\mathrm{r}_{2}\right)=\mathrm{L}\left(\mathrm{r}_{...

A machine is represented by states $Q$, input alphabet $\sum$, transition function $\delta$. Initial state $q_{0}$ and final state $F$. The machine accepts all the string...

Which of the following is a property of a regular language?It cannot be represented by a finite automaton.It cannot be represented by a regular expression.It can only be ...

Can someone provide a formal proof for such questions?

(11+0)*×(00+1)* convert this regular expression into finite automata

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...

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 ...

Find regular expression for the following language L= {w: |w| mod 5 ≠ 0}

What is the DFA for the regular expression:- (a+b)* b (a+b)*

Is this regular expression is correct for the Language = { w| number of a's in the string = 0 mod 3} on $\Sigma=\{a,b\}$

Most languages are case sensitive, so keywords can be written only one way, and the regular expressions describing their lexemes are very simple. However, some languages,...