题目:​​原题链接​(中等)

标签:树、二叉树、深度优先搜索

解法

时间复杂度

空间复杂度

执行用时

Ans 1 (Python)

O(N)

O(N)

68ms (58.44%)

Ans 2 (Python)

Ans 3 (Python)

解法一:

class Solution:
def removeLeafNodes(self, root: TreeNode, target: int) -> TreeNode:
def dfs(node):
if node.left and dfs(node.left):
node.left = None
if node.right and dfs(node.right):
node.right = None
return not node.left and not node.right and node.val == target

dfs(root)

if not root.left and not root.right and root.val == target:
return None

return root