Regular Expression
Q11.
Consider the regular expression R = (a + b)^* (aa + bb) (a + b)^* Which of the following non-deterministic finite automata recognizes the language defined by the regular expression R? Edges labeled \lambda denote transitions on the empty string.Q12.
The length of the shortest string NOT in the language (over \Sigma={a,b}) of the following regular expression is _________. a*b* (ba)* a*Q13.
In some programming language, an identifier is permitted to be a letter followed by any number of letters or digits. If L and D denote the sets of letters and digits respectively, which of the following expressions defines an identifier?Q14.
Which one of the following languages over the alphabet {0,1} is described by the regular expression: (0+1)*0(0+1)*0(0+1)*?Q16.
Let L=\left\{w \in(0+1)^{*} \mid w \text { has even number of } 1 \text { 's }\right\}, i.e. L is the set of all bit strings with even number of 1's. Which one of the regular expression below represents L?Q17.
Let L = {w \in (0 + 1)*|w has even number of 1s}, i.e. L is the set of all bit strings with even number of 1s. Which one of the regular expressions below represents L?Q19.
Let S and T be languages over \Sigma=\{a.b\} represented by the regular expressions (a+b^*)^* \text{ and } (a+b)^*, respectively. Which of the following is true?