On Wed, Jan 21, 2015 at 10:20 PM, Rustom Mody <rustompm...@gmail.com> wrote: > On Thursday, January 22, 2015 at 4:25:03 AM UTC+5:30, Ian wrote: >> On Tue, Jan 20, 2015 at 6:23 PM, Rustom Mody wrote: >> > The Haskell is bullseye¹ in capturing the essense of a tree because >> > conceptually a tree of type t is recursive in the sense that it can contain >> > 2 subtrees -- (B x lst rst) -- or its a base case -- L x. >> >> How do you create a tree containing an even number of elements under >> this constraint? > > Not sure what you are asking... > > [And a text only group makes discussing pictur-esque things hard] > What do you mean by 'element'? > Leaf? Internal? Either?
By "element" I mean an individual datum contained in the tree. Likewise the elements of a list are its contents. Since each element is associated with a node, the question could equally be phrased as "How do you create a tree containing an even number of elements under this constraint?" The point I was driving at is that the definition is incomplete -- in addition to being an internal node or a leaf, a tree can also be empty. In fact I would suggest that an empty tree should be the real base case, since what is a leaf node but a node where both of its children are empty trees? -- https://mail.python.org/mailman/listinfo/python-list
