NO CLASS THURSDAY 6/18 (see you Monday)

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 Tree Data Structure

 Nodes have two pointers: LEFT and RIGHT

  if LEFT and RIGHT are both 0, the node
    is a "leaf node"

  every tree has a "root" node

  from the "root" node, every other node
    is accessible

  a "subtree" is a subset of a tree and
    is itself a tree

  a "tree" has NO loops (i.e. not circular)


  e.g. implement set<int>
  e.g. insert (in order):
          4, 9, 3, 13, 19, 7, 11

      add_to_tree( int value, Tree * root )

        see powerpoint pictures