
Xkcd: Tree (humor) - tswicegood
http://xkcd.com/835/
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iwwr
That looks like a sparse tree, but what are the rules about coloring the nodes
red or green? What about the special case root (yellow)?

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ggchappell
Good question. I figured the obvious thing to do would be a red-black (or
green in this case) tree, but that isn't one.

Also, what about the "heap"? When people say "heap", they usually mean a
Binary Heap, but the tree of presents is not a Binary Heap. It is also not a
Binomial Heap. It might be a possible state of a Fibonacci Heap; I'm not sure.

