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**Assigned:**
Wed 2 Dec 2009

**Due:**
Wed 09 Dec 2009

- Please review the course syllabus and make sure that you understand the course policies for grading, late homework, and academic honesty.
- On the
*first page*of your solution write-up, you*must*make explicit which problems are to be graded for "regular credit", which problems are to be graded for "extra credit", and which problems you did not attempt. Please use a table something like the followingProblem 01 02 03 04 05 06 07 08 09 ... Credit RC RC RC EC RC RC NA RC RC ... where "RC" is "regular credit", "EC" is "extra credit", and "NA" is "not applicable" (not attempted). Failure to do so will result in an arbitrary set of problems being graded for regular credit, no problems being graded for extra credit, and a five percent penalty assessment.

- You must also write down with whom you worked on the assignment. If this changes from problem to problem, then you should write down this information separately with each problem.

**Required:** problem 1; one of problems 2 and 3; one of problems 4 and 5; one of problems 6 and 7; one of problems 8 and 9

**Points:** Problems are worth 20 points each.

Unless otherwise indicated, problems are from *Algorithms* by Dasgupta, Papadimitriou, and Vazirani.

- 5.28
- 6.1
- 6.2
- 6.4
- 6.7
(Hint: Let
*L(i,j)*the length of the longest palindromic subsequence of string*x*[*i, ... , j*].) - 6.17, 6.18
- 6.22
- 6.21 (Hint: It helps to think of T as a rooted tree with subtrees as subproblems.)
- 6.26

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The URL for this document is: http://www.ccs.neu.edu/home/fell/CS4800/F09/Homework/hw.10.html