## 1. Find out the regular expression for the set of strings of a’s, b’s and c’s (aaa, aab, .. .. .. .., ccc).

Solution:

We have the input alphabets ∑ = {a, b, c}

Here, the resultant regular expression will denote any string from the given set (aaa, aab, .. .. .. .. , ccc). Thus, the resultant regular expression can be simply written as-

[a | b | c] [a | b | c] [a | b | c]

or,

[a + b + c] [a + b + c] [a + b + c]

or

[a ∪ b ∪| c] [a ∪ b ∪ c] [a ∪ b ∪ c]