CS 6604, Assignment 3 - Due February 25, 2008

Please show your work

  1. Suppose an LZ77 decoder with source alphabet {a, b} is to decode the sequence (0,0,b), (0,0,a), (2,1,b), (3,3,a), (3,1,a), (7,6,b), (1,2,-), where the dash in the last code indicates that there are no more characters in the string. Compute the decoded string.

  2. Suppose an LZ78 decoder with source alphabet {a, b} is to decode the sequence (0,a), (0,b), (2,b), (1,a), (1,b), (5,b), (4,b), (7,-), where the dash in the last code indicates that there are no more characters in the string. Compute the decoded string.

  3. Suppose an LZW decoder with source alphabet {a, b} is to decode the sequence 0, 2, 1, 3, 0, 4, 1, 8, 9. Compute the decoded string.