CS141 Lab 10

Class Webpage:  http://www.cs.ucr.edu/~jiang/141-homepage.html

For the labs of the tenth week:

• Go over the  third homework solutions.

• Go over selected items in the  final exam review.

• Using an example similar to CLRS, p. 925, Fig. 32.11 to show how to compute the prefix/failure function and how to use the function in KMP using a diagram similar to the one (an additional page) given in class.

• For what kind of patterns/texts is BM faster than KMP, and when is KMP faster than BM, assuming that the the prefix function and lookup table are precomputed?

• In-lab exercise: Implement the KMP algorithm given in CLRS, p. 926, and test it on some random texts and patterns. Output the number of (character) comparisons in each test.

TA: Provide some test data with correct numbers of comparisons. Keep track of which students completed the exercise.

• For keen students:

  Modify the KMP search algorithm given in class to find all the occurrences of the pattern in Theta(n) time (don't peek at the algorithm in CLRS :-) How do you argue that your algorithm really runs in Theta(n) time?