226.翻转二叉树给你一棵二叉树的根节点 root 翻转这棵二叉树并返回其根节点。示例 1输入root [4,2,7,1,3,6,9]输出[4,7,2,9,6,3,1]示例 2输入root [2,1,3]输出[2,3,1]示例 3输入root []输出[]提示树中节点数目范围在 [0, 100] 内-100 Node.val 100实现代码Python:fromcollectionsimportdeque# Definition for a binary tree node.# class TreeNode:# def __init__(self, val0, leftNone, rightNone):# self.val val# self.left left# self.right rightclassSolution:definvertTree(self,root:Optional[TreeNode])-Optional[TreeNode]:ifnotroot:returnroot queuedeque([root])whilequeue:sizelen(queue)for_inrange(size):nodequeue.popleft()ifnode.leftornode.right:tmpnode.left node.leftnode.right node.righttmpifnode.left:queue.append(node.left)ifnode.right:queue.append(node.right)returnroot分析借助层序遍历实现
力扣刷题——226.翻转二叉树
发布时间：2026/7/13 22:20:16
226.翻转二叉树给你一棵二叉树的根节点 root 翻转这棵二叉树并返回其根节点。示例 1输入root [4,2,7,1,3,6,9]输出[4,7,2,9,6,3,1]示例 2输入root [2,1,3]输出[2,3,1]示例 3输入root []输出[]提示树中节点数目范围在 [0, 100] 内-100 Node.val 100实现代码Python:fromcollectionsimportdeque# Definition for a binary tree node.# class TreeNode:# def __init__(self, val0, leftNone, rightNone):# self.val val# self.left left# self.right rightclassSolution:definvertTree(self,root:Optional[TreeNode])-Optional[TreeNode]:ifnotroot:returnroot queuedeque([root])whilequeue:sizelen(queue)for_inrange(size):nodequeue.popleft()ifnode.leftornode.right:tmpnode.left node.leftnode.right node.righttmpifnode.left:queue.append(node.left)ifnode.right:queue.append(node.right)returnroot分析借助层序遍历实现
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