Don't copy answers from other ones
it's different question Look carefully thanks
Describe the strings in the set S of strings over the alphabet ?= {a, b, c} defined recursively
by (1) c ? S and (2) if x ? S then xa ? S and xb ? S and cx ?S.
Hint: Your description should be a sentence that provides aneasy test to check if a given string is in the set or not. Anexample of such a description is: S consists of all strings of a’s,b’s, and c’s, with more a’s than b’s. That isn’t a correctdescription since cab is in S and doesn’t have more a’s than b’s,and also baac isn’t in S, but does have more a’s than b’s. So thatattempted description is really terrible. The best way to do thisproblem is to use the rules to build a bunch of strings in S untila suitable description becomes obvious.
