Two CS problems:

1)

2)

Any help appreciated!

L = {S:S is of the form A'B2n, for some n > 0} Thus, a string is in L if and only if it starts with a sequence of A's and is followed by a sequence of twice as many B's. For example, AABBBB is in L, but ABBB, ABBABB, and the empty string are not. a. Give a grammar for the language L b. Write a recursive function that determines whether the string strExp is in L