End of trees:
	I finished the destructor
	Found three bugs:
		1.  Ordering bug
		2.  Parent not set in some cases
		3.  New node might have moved with rebalance

Anyway, after that, I think it works

Can we use a tree for sorting?
	Put everything to sort in a tree
	Do an inorder traversal

Running time!
	How would it be?  Analysis.
	Did we avoid n squared?  If so, it should scale ok
		Let's try it vs. bubble sort
		We'll just steal pieces from the quicksort demo

Note:  We didn't do deletion from the tree demo
	It's really just another round of the same stuff

Heaps!


"The heap" vs. "A heap":
	"The heap" is where we obtain dynamically-allocated memory
	"A heap" is a specialized tree-based data structure
	They're not related
	"The heap" is more like "junk heap" or whatnot
	
A heap is NOT a binary search tree!
	Unlike red-black and AVL

The heap property:
	Children are no greater than their parents
	Therefore the no node is greater than the root
		In a max-heap anyway.  min-heap is the opposite

A heap is a common way to implement a priority queue
	priority queue:  to-do items are sorted by priority
		Not FIFO or LIFO

It's possible to have a non-binary heap, but we'll assume a binary heap

Heap operations (Let's add on scaling):
	find-max    O(1)
	insert      O(log(n))
	delete-max  O(log(n))
	search		O(n)

Why would you want a heap?
	Schedule writes to a hard drive, or some other device
	Sorting (heapsort)
	Anything where you have to deal with an unsorted collection in order		

Structure property:  Each level is completely filled except the last
	last is filled left to right
	More strict than AVL

Insertion:  
	Insert at leaf
	Swap with parent until heap property is restored

Removing root:
	Greatest parent replaces root
	Recursively apply to child's node
	At leaf, copy last leaf to empty spot and check with parent

Implementation:
	Usually an array, actually!
	Can you flatten a tree?
		Don't hurt it!
	Example

Alright:  Can we do it?
	Starting out:  Let's take a look at last term's example
		Did it even work?
		It wasn't a dynamically-linked data structure
		Question:  Is a sorted array a heap, for that structure?
	Project 3 will be a heap project