# CMPSCI 250: Introduction to Computation

### David Mix Barrington

### Spring, 2005

# Homework Assignment #6

#### Posted Monday 11 April 2005

#### Due on paper in class, Wednesday 20 April 2005

There are ten questions for 100 total points plus 20 extra credit. All are from
the textbook, *A
Mathematical Foundation for Computer Science*. "Problem 1.1.2", for
example, is at the end of Section 1.1 and is labeled "P1.1.2".
The number after each problem is its individual point value. Make sure
you don't do an Exercise when a Problem is assigned! (Though the Exercises
should be good practice and the answers to them are in the back of the book.)

Students are responsible for understanding and following
the academic honesty
policies indicated on this page.

Pages 6-38: Problem 6.7.1 (20)

Pages 6-42: Writing Exercise 5 (20 extra credit). For full credit you must also,
Using the given methods,
write a `void`

method to list all permutations for a given `n`

and `k`

. Note that the variables `n`

and `k`

need
to be `static`

(class variables rather than instance variables),
and there needs to be a method to set them. Compiling and running your code is not
absolutely required but may be the best way to convince us your solution is correct.
(The
Discussion #9 solution, to be posted
Wed 13 April, may help with this.)

Pages 6-47: Problems 6.9.1 (10) and 6.9.3 (10)

Page 6-55: Problem 6.10.5 (10)

Page 7-28: Problems 7.6.2 (5), 7.6.3 (20), and 7.6.4 (part a only) (5)

Pages 7-35 and 7-36: Problems 7.7.2 (part a only) (10) and 7.7.5 (part c only) (10)

Last modified 11 April 2005