The document discusses different data structures: a queue, which follows FIFO (first in, first out) where the first item joined is the first served; a stack, which follows LIFO (last in, first out) where the last item joined is the first served; and a heap, which is a tree structure where lower values are near the bottom and higher values towards the top.

1. Damian Gordon

2.  What is a queue?

3.  What is a queue?

4.  What is a queue?
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5.  What is a queue?
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6.  What is a queue?
 It’s a structure that conforms to the principle
of First In, First Out (FIFO).
 The first item to join the queue is the first
item to be served.

7.  What is a stack?

8.  What is a stack?
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9.  What is a stack?
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10.  What is a stack?
 It’s a structure that conforms to the principle
of Last In, First Out (LIFO).
 The last item to join the stack is the first item
to be served.

11.  What is a heap?

12.  What is a heap?

13.  What is a heap?
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14.  What is a heap?
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15.  What is a heap?
 A heap is a tree-like structure generally each
node has two children nodes, where the lower
values are stored near the bottom of the tree
and higher values towards the top of the tree.

16.  What is a heap?
 MORE FORMALLY:
 The heap property:
◦ If A is a parent node of B then the key of node A is
ordered with respect to the key of node B with the
same ordering applying across the heap

17.  What is a queue?
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18.  What is a queue?
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19.  What is a stack?
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20.  What is a stack?
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21.  What is a heap?
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22.  What is a heap?
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Based on value not location