regular expression for the language L = { w ∈ {0,1}* | w has no pair of…
2013
regular expression for the language L = { w ∈ {0,1}* | w has no pair of consecutive zeros } is
- A.
(1 + 010)*
- B.
(01 + 10)*
- C.
(1 + 010)* (0 + ε)
- D.
(1 + 01)* (0 + ε)
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Correct answer: D
To construct a regular expression for binary strings without consecutive zeros, consider valid blocks. Every zero must be followed by a one unless it is the last character. This allows repeating patterns of '1' or '01'. The expression (1 + 01)* covers these internal blocks. Finally, allow an optional trailing zero with (0 + ε). Thus, the regex is (1 + 01)*(0 + ε).
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