return
if root.right and root.left:
traverse_to_next(root.left).right = root.right
if root.left:
root.right = root.left
root.left = None
if root.right:
self.flatten(root.right)
def traverse_to_next(root: TreeNode) -> None:
while True:
while root.right:
root = root.right
if root.left:
root = root.left
else:
return root
root = TreeNode.from_array([1, 2, 5, 3, 4, Empty, 6])
expected = TreeNode(1)
current = expected
for i in range(2, 7):
current.right = TreeNode(i)
current = current.right
Solution().flatten(root)
assert TreeNode.subtrees_match(root, expected)
return root.max_seen
# rob the root
choice_1_value = root.val
if root.left and root.left.left:
choice_1_value += self.rob(root.left.left)
if root.left and root.left.right:
choice_1_value += self.rob(root.left.right)
if root.right and root.right.left:
choice_1_value += self.rob(root.right.left)
if root.right and root.right.right:
choice_1_value += self.rob(root.right.right)
# don't rob the root
choice_2_value = 0
if root.left:
choice_2_value += self.rob(root.left)
if root.right:
choice_2_value += self.rob(root.right)
maximum = max(choice_1_value, choice_2_value)
root.max_seen = maximum
return root.max_seen
tree = TreeNode.from_array([3, 2, 3, TreeNode.EMPTY, 3, TreeNode.EMPTY, 1])
print(Solution().rob(tree))
tree2 = TreeNode.from_array([3, 4, 5, 1, 3, TreeNode.EMPTY, 1])
print(Solution().rob(tree2))
