def testBST():
bst1 = BinarySearchTree()
n=int(raw_input("Enter number of elements: "))
for i in range(n):
bst1.insertElement(int(raw_input()))
print "INORDER:"
bst1.inorderTraverse(bst1.root)
print
print "PREORDER:"
bst1.preorderTraverse(bst1.root)
print
print "POSTORDER:"
bst1.postorderTraverse(bst1.root)