#!/usr/bin/env gbs3

Class TreeNode

  Public Left As TreeNode
  Public Right As TreeNode

  Static Public Sub Create(D As Integer) As TreeNode

    Return ChildTreeNodes(D)

  End

  Static Public Sub ChildTreeNodes(D As Integer) As TreeNode

    Dim hNode As TreeNode = new TreeNode

    If D > 0 Then

      hNode.Left = ChildTreeNodes(D - 1)
      hNode.Right = ChildTreeNodes(D - 1)

    Endif

    Return hNode

  End

  Public Sub Check() As Integer

    If Not Left Then Return 1
    Return Left.Check() + Right.Check() + 1

  End

End Class

Dim iMinDepth As Integer = 4
Dim iMaxDepth As Integer = 16
Dim iStretchDepth As Integer = iMaxDepth + 1
Dim iCheck As Integer
Dim hTree As TreeNode
Dim D, I As Integer
Dim iIterations As Integer

iCheck = TreeNode.Create(iStretchDepth).Check()

Print "stretch tree of depth "; iMaxDepth + 1; "\t check: "; iCheck

hTree = TreeNode.Create(iMaxDepth)

For D = iMinDepth To iMaxDepth Step 2

  iCheck = 0
  iIterations = Shl(1, iMaxDepth - D + iMinDepth)

  For I = 1 To iIterations

    iCheck += TreeNode.Create(D).Check()

  Next

  Print iIterations;"\t trees of depth "; D; "\t check: ";iCheck

Next

Print "long lived tree of depth "; iMaxDepth; "\t check: "; hTree.Check()

Error CStr(Jit.Time)