三个二叉树的简单问题

来源：互联网发布：赵薇被泼粪事件,知乎编辑：程序博客网时间：2024/05/29 04:23

本文给出三个二叉树的简单问题的答案，因其简单易懂，笔者就不多说了，直接上代码。

一.找出二叉树最大值的节点

//找出二叉树最大值的节点class Solution {public:    /**     * @param root the root of binary tree     * @return the max node     */    TreeNode* maxNode(TreeNode* root) {        if (root == NULL) return root;        TreeNode* leftMax = root;        TreeNode* rightMax = root;        if (root->left != NULL) leftMax = maxNode(root->left);        if (root->right != NULL) rightMax = maxNode(root->right);        TreeNode* max = root;        if (leftMax->val > max->val) max = leftMax;        if (rightMax->val > max->val) max = rightMax;        return max;    }};

二.深度复制一个二叉树

//深度复制一个二叉树/** * Definition of TreeNode: * class TreeNode { * public: *     int val; *     TreeNode *left, *right; *     TreeNode(int val) { *         this->val = val; *         this->left = this->right = NULL; *     } * } */class Solution {public:    /**     * @param root: The root of binary tree     * @return root of new tree     */    TreeNode* cloneTree(TreeNode *root) {        if (root == NULL) return NULL;        TreeNode* r = new TreeNode(root->val);        if (root->left != NULL) r->left = cloneTree(root->left);        if (root->right != NULL) r->right = cloneTree(root->right);        return r;    }};

三.找出二叉树的最大深度

二叉树的深度为根节点到最远叶子节点的距离。

//找出二叉树的最大深度/** * Definition of TreeNode: * class TreeNode { * public: *     int val; *     TreeNode *left, *right; *     TreeNode(int val) { *         this->val = val; *         this->left = this->right = NULL; *     } * } */class Solution {public:    /**     * @param root: The root of binary tree.     * @return: An integer     */    int maxDepth(TreeNode *root) {        if (root == NULL) return 0;        int left = maxDepth(root->left);        int right = maxDepth(root->right);        if (left >= right) return left+1;        else return right+1;    }};

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