Exam2Grading

Exam2Grading - BCB 567/CprE 548 Fall 2007 Exam 2 Solutions...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: BCB 567/CprE 548 Fall 2007 Exam 2 Solutions 1. (a) This is true. Consider that LCP [ i ] = k . This means that suffix SA [ i ] and suffix SA [ i + 1] have a longest common prefix of length k . This implies that suffixes SA [ i ] + 1 and SA [ i + 1] + 1 have a longest common prefix of k- 1. This means that the range minimum in the LCP array between indexes INV [ SA [ i ] + 1] and INV [ SA [ i + 1] + 1] is k- 1. However, for this to be true, there must be some entry in the LCP array equal to k- 1. (b) The maximum zero entries in the LCP is equal to the alphabet size (if you consider the last entry of the LCP array) or alphabet size - 1 if you do not. Think about a dictionary and how many times the first letter changes. Grading Notes: Both Σ and Σ- 1 received full credit. Because the alphabet size can be at most N , the answers N or N- 1 received partial credit. (c) The minimum number of occurrences is 6. For each incoming suffix link, there exists some internal node with path label cα . Therefore, cα occurs at least twice. Because there are 3 suffix links, we have at least 3 × 2 = 6 occurrences. (d) i. No, counter example: ABC and ABCAB ii. No, counter example: ABC and ABCAB iii. Yes iv. No, counter example: ABC and ABCAB 2. (a) – (b) – (c) i. To find length 3 repeats in the look-up table, search for table entries with more than one index.than one index....
View Full Document

This note was uploaded on 10/01/2009 for the course CS BCB/Co taught by Professor Olivereulenstein during the Fall '06 term at Iowa State.

Page1 / 2

Exam2Grading - BCB 567/CprE 548 Fall 2007 Exam 2 Solutions...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online