def invertTree(self, root: TreeNode) -> TreeNode:
"""Inverts a binary tree
Args:
root: root node of the tree
Return:
root node of the inverted tree
"""
queue = Queue(root)
if not root:
return None
while queue:
node = queue.node
temp = node.left
node.left = node.right
node.right = temp
if node.left:
queue.addToQueue(node.left)
if node.right:
queue.addToQueue(node.right)
queue = queue.popQueue()
return root
# main
tree = toBinaryTree([4, 2, 7, 1, 3, 6, 9])
printTree(tree)
print("==================")
sol = Solution()
printTree(sol.invertTree(tree))
def kthSmallestRecursive(self, root: TreeNode, k: int) -> int:
self.k = k
return self.findKthInorder(root)
def kthSmallestIterative(self, root: TreeNode, k: int) -> int:
"""Finds the kth smallest element in a binary tree
Args:
root: TreeNode binary tree
k: integer representing the smallest number in root
Returns:
The kth TreeNode value
"""
stack = []
while root or stack:
while root:
stack.append(root)
root = root.left
root = stack.pop()
k -= 1
if k == 0:
return root.val
root = root.right
# main
tree = toBinaryTree([3, 1, 4, None, 2])
printTree(tree)
sol = Solution()
smallest = sol.kthSmallestIterative(tree, 1)
print(smallest)
return False
if s.val != t.val:
return False
return (self.checkAll(s.left, t.left)
and self.checkAll(s.right, t.right))
def isSubtree(self, s: TreeNode, t: TreeNode) -> bool:
"""
Check if a tree is a subtree of another tree
Args:
s: binary tree
t: binary tree (subtree)
Return:
True or False
"""
if not s or not t:
return False
if self.checkAll(s, t):
return True
return self.isSubtree(s.left, t) or self.isSubtree(s.right, t)
# main
tree1 = toBinaryTree([3, 4, 5, 1, 2])
tree2 = toBinaryTree([4, 1, 2])
printTree(tree1)
printTree(tree2)
sol = Solution()
print(sol.isSubtree(tree1, tree2))