Representation of Trees

MultiwayTree.py

    """
    >>> Tree = test_listing_2_8()
    >>> t = Tree(Tree("a", Tree("b", Tree("c", Tree("d")))))
    >>> t.kids.next.next.val
    'c'
    """
    class Tree:
        def __init__(self, kids, next=None):
            self.kids = self.val = kids
            self.next = next

SimpleTree.py

    """
    >>> Tree = test_listing_2_7()
    >>> t = Tree(Tree("a", "b"), Tree("c", "d"))
    >>> t.right.left
    'c'
    """
    class Tree:
        def __init__(self, left, right=None):
            self.left = left
            self.right = right