Homework 3
Due 29 September, 2016
Give reasons for all answers.
- Show how LZ77 encodes the string TENTENNESSEETENTS if the search
buffer has length 8 and the lookahead buffer has length 4. Show that
your encoding decodes correctly.
- Encode and decode the same string with LZ78.
- Encode and decode the same string with LZW with initial dictionary
entries E, N, S, T numbered 1, 2, 3, 4 respectively.
- In class we saw that LZ77 can encode a long repeating pattern
as a single codeword, up to the length permitted by the search and
lookahead buffers. What happens with LZ78 if it encounters a long
repetition of the same character?