====== Homework 3 ======
//Due: 28 Nov 2008//

  - Exercises 1.15, <del>1.19</del>, 1.21, 1.28.
  - Problem 1.46(a,c,d)  (Hint: for 1.46c, you can use the fact that the complement of a regular language is regular.)
  - Problem 1.53, 1.54.
  - Problem 1.24, 1.25, 1.26.  (These are related to what we have done in class: DFAs that produce output.)