| 5. |
(a) Identify and explain the
difference between a stack and queue abstract data-type. |
[2] |
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(b) Given the following type
definition for a queue: |
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Where Front points to the first element in the
queue and Rear points to the last element added to the queue. It is assumed that the Next
field of a Node points from newer elements in the queue to older ones. |
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(i) Write a function sizeQueue that
takes a queue of type QueueType as its argument, and returns an integer that identifies
the number of elements in the queue. |
[5] |
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(ii) Write a procedure enQueue that
takes two arguments: (i) a queue of type QueueType; and (ii) an integer to be added to the
queue. The effect of the procedure is to alter the queue argument by adding the integer
parameter to the queue. |
[6] |
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(iii) Write a procedure deQueue that
takes a non-empty queue of type QueueType as its argument. The effect of the
procedure is to alter the queue by removing an element. |
[7] |