def test_invalidTreeIsNotBST(self):
root = TreeNode(20)
root.left = TreeNode(10)
root.right = TreeNode(30)
root.right.left = TreeNode(5)
root.right.right = TreeNode(40)
self.assertFalse(is_bst(root))
def test_validBinaryTreeIsValid(self):
root = TreeNode(5)
root.left = TreeNode(3)
root.right = TreeNode(7)
root.left.left = TreeNode(1)
root.left.right = TreeNode(4)
root.right.left = TreeNode(6)
self.assertTrue(is_bst(root))
def remove_by_recursion(self, value):
if not self.root:
return False
elif value == self.root.data:
temp_root = TreeNode() # 创建一个临时节点 方便处理
temp_root.left = self.root
ret = BinarySearchTree.__remove__(temp_root.left, temp_root, value)
self.root = temp_root.left
return ret
elif value < self.root.data and self.root.left:
return BinarySearchTree.__remove__(self.root.left, self.root, value)
elif value > self.root.data and self.root.right:
return BinarySearchTree.__remove__(self.root.right, self.root, value)
return False
