Do all of the following.

  1. The alphabet for all these examples is {b,p,d}

    1. 2 or more b followed by one or more of ( either ( p followed by zero or one of p ) or ( d followed by b followed by p ) ) followed by exactly 5 d's followed by exactly 1 p's
    2. all strings that do not contain the substring dpdb
    3. starts with 6 or more pbp's, ends with 3 or more dd's, and does not contain the substring pd.
  2. For the next questions, use the following signature

    signature lab02 = sig
        type `a seq
        create `a seq
        pull `a seq -> `a
        push `a * `a seq -> `a seq
        dup `a seq -> `a seq
        nada `a seq -> bool
    end
    1. What is the type of
      1. dup
      2. nada(create)
      3. pull (create)
      4. pull (dup )
      5. pull (push )
      6. push (dup (push (1, lab02.create)),lab02.create)
      7. push (nada(create)), create)

      where the lab02.xxx notation means that a new instance of the module is used every time -- in other words, the `a are independent

    2. What is the value (if any) of
      1. push (2, push (3, create))
      2. nada(create)