110. 平衡二叉树 110. Balanced Binary Tree 题目描述 给定一个二叉树,判断它是否是高度平衡的二叉树. 本题中,一棵高度平衡二叉树定义为: 一个二叉树每个节点的左右两个子树的高度差的绝对值不超过 1. 每日一算法2019/5/18Day 15LeetCode110. Balanced Binary Tree 示例 1: 给定二叉树 [3,9,20,null,null,15,7] 3 / \ 9 20 / \ 15 7 返回 true. 示例 2: 给定二叉树 [1,2…
问题 给出一棵二叉树,判断它是否在高度上是平衡的. 对于本问题,高度上平衡的二叉树定义为:每个节点的两棵子树的深度差永远不大于1的一棵二叉树. 初始思路 根据定义,思路应该比较直接:递归计算每个节点左右子树的深度,只要发现一次深度差大于1的情况,即可终止递归返回不平衡的结果.最终代码如下: class Solution { public: bool isBalanced(TreeNode *root) { if(!root) { return true; } isBalanced_ = true…
平衡二叉树(Balanced Binary Tree 或 Height-Balanced Tree)又称AVL树 (a)和(b)都是排序二叉树,但是查找(b)的93节点就需要查找6次,查找(a)的93节点就需要查找3次,所以(b)的效率不高. 平衡二叉树(Balanced Binary Tree 或 Height-Balanced Tree)又称AVL树.它或者是一颗空树,或者是具有下列性质的二叉树:它的左子树和右子树的深度只差的绝对值不超过1.若将二叉树上节点的平衡因子BF(Balance F…
Given a binary tree, determine if it is height-balanced. For this problem, a height-balanced binary tree is defined as a binary tree in which the depth of the two subtrees of every node never differ by more than 1. 就是去查看一棵树是不是平衡的,一开始对平衡二叉树的理解有错误,所以写错…
题目 Given a binary tree, determine if it is height-balanced. For this problem, a height-balanced binary tree is defined as a binary tree in which the depth of the two subtrees of every node never differ by more than 1. 分析 判断给定二叉树是否为二叉平衡树,即任一节点的左右子树高度差…
Problem Link: http://oj.leetcode.com/problems/balanced-binary-tree/ We use a recursive auxilar function to determine whether a sub-tree is balanced, if the tree is balanced, it also return the depth of the sub-tree. A tree T is balanced if the follow…
Given a binary tree, determine if it is height-balanced. For this problem, a height-balanced binary tree is defined as: a binary tree in which the depth of the two subtrees of every node never differ by more than 1. Example 1: Given the following tre…
[抄题]: Given a binary tree, determine if it is height-balanced. For this problem, a height-balanced binary tree is defined as: a binary tree in which the depth of the two subtrees of every node never differ by more than 1. [思维问题]: 以为要用traverse一直判断,结果发…
这是悦乐书的第167次更新,第169篇原创 01 看题和准备 今天介绍的是LeetCode算法题中Easy级别的第26题(顺位题号是110).给定二叉树,判断它是否是高度平衡的.对于此问题,高度平衡二叉树定义为:一个二叉树,其中每个节点的两个子树的深度从不相差超过1.例如: 给定以下树[3,9,20,null,null,15,7]: 3 / \ 9 20 / \ 15 7 返回true. 给定以下树[1,2,2,3,3,null,null,4,4]: 1 / \ 2 2 / \ 3 3 / \…
1.题目描述 2.问题分析 DFS. 3.代码 bool isBalanced(TreeNode* root) { if (root == NULL) return true; && isBalanced(root->left) && isBalanced(root->right); } int height(TreeNode *node) { if (node == NULL) ; if (node->left == NULL && no…