15 views

Write regular expressions for the following languages$:$

1. The set of all strings of $0's$ and $1's$ not containing $101$ as a substring.
2. The set of all strings with an equal number of $0's$ and $1's,$ such that no prefix has two more $0'$ than $1's,$ nor two more $1's$ than  $0's.$
3. The set of strings of $0's$ and $1's$ whose number of $0's$ is divisible by five and whose number of $1's$ is even.

edited | 15 views