from helpers.py.tree_node import TreeNode, TreeNodeOperation
class Solution:
def mirrorTree(self, root: TreeNode) -> TreeNode:
if not root:
return None
root.left, root.right = self.mirrorTree(root.right), self.mirrorTree(
root.left)
return root
if __name__ == '__main__':
test_cases = [[4, 2, 7, 1, 3, 6, 9]]
for case in test_cases:
case = TreeNodeOperation().create_binary_tree(case)
ans = Solution().mirrorTree(case)
TreeNodeOperation().print(ans)
class Solution:
"""
倒序中序遍历
"""
def __init__(self):
self.k = 0
self.ans = None
def kthLargest(self, root: TreeNode, k: int) -> int:
def post_order(root: TreeNode):
if not root:
return
post_order(root.right)
self.k -= 1
if self.k == 0:
self.ans = root.val
post_order(root.left)
self.k = k
post_order(root)
return self.ans
if __name__ == '__main__':
test_cases = [[[3, 1, 4, None, 2], 1], [[5, 3, 6, 2, 4, None, None, 1], 3]]
for case in test_cases:
case[0] = TreeNodeOperation().create_binary_tree(case[0])
ans = Solution().kthLargest(*case)
print(ans)
from helpers.py.tree_node import TreeNode, TreeNodeOperation
class Solution:
def isSubStructure(self, A: TreeNode, B: TreeNode) -> bool:
def recur(A, B):
if not B:
return True
if not A or A.val != B.val:
return False
return recur(A.left, B.left) and recur(A.right, B.right)
return bool(A and B) and (recur(A, B) or self.isSubStructure(
A.left, B) or self.isSubStructure(A.right, B))
if __name__ == '__main__':
test_cases = [[[1, 2, 3], [3, 1]], [[3, 4, 5, 1, 2], [4, 1]]]
for case in test_cases:
case[0] = TreeNodeOperation().create_binary_tree(case[0])
TreeNodeOperation().print(case[0])
TreeNodeOperation().pre_order(case[0])
case[1] = TreeNodeOperation().create_binary_tree(case[1])
TreeNodeOperation().print(case[1])
ans = Solution().isSubStructure(*case)
print(ans)