CGS 3460 - Programming Using C
Summer 2009
Assignment #9
20 Points
Assigned: 07/24/2009, Friday
Due: 07/30/2009, Thu, 11:59 PM
For this assignment, there is a single project. We will being implementing an abstract
data type known as a double ended queue(DEQUE). You may want to check out
http://en.wikipedia.org/wiki/Double-ended_queue for more information on the DEQUE.
Also note that the implementation of a similar abstract data type, known as a stack is
discussed in the book in chapter 19.
The DEQUE will contain integers and have no limit on the size. You will define your
DEQUE in files called deque.h and deque.c. All variables used should be accessible only
to functions defined in deque.c.(i.e., we should not be able to access any of your
variables in main.)
The following functions should be defined so that we can modify the DEQUE from main.
They should be declared in deque.h and defined in deque.c. You may add any additional
“helper” functions you wish, however, we should not be able to call your helper functions.
Note that limiting access to a variable or a function in your deque.c file is as simple as
applying a certain key word.
void addToFront(int v); - Adds the given value to the front of the queue. Note, if you
decide to use a dynamic array to keep track of the elements in your DEQUE and the
number of elements in your DEQUE becomes larger than the array size, you will need to
create a new array that is large enough to hold the number of elements in your queue,
copy the elements from the old array to the new one, and use the new array to hold the
elements.
void addToBack(int v); - Adds the given value to the back of the queue. Note, if you
decide to use a dynamic array to keep track of the elements in your DEQUE and the
number of elements in your DEQUE becomes larger than the array size, you will need to
create a new array that is large enough to hold the number of elements in your queue,
copy the elements from the old array to the new one, and use the new array to hold the
elements.
int removeFromFront(); - Removes the element at the front of the queue and returns
it. If the DEQUE is empty, it returns -1.
int removeFromBack(); - Removes the element at the back of the queue and returns it.
If the DEQUE is empty, it returns -1.
int checkFront(); - Returns the element at the front of the queue, but does not remove
it. If the DEQUE is empty, it returns -1.
int checkBack(); -Returns the element at the back of the queue, but does not remove it.
If the DEQUE is empty, it returns -1.
