给出一个完全二叉树,求出该树的节点个数.完全二叉树的定义如下:在完全二叉树中,除了最底层节点可能没填满外,其余每层节点数都达到最大值,并且最下面一层的节点都集中在该层最左边的若干位置.若最底层为第 h 层,则该层包含1~ 2h 个节点.详见:https://leetcode.com/problems/count-complete-tree-nodes/description/ Java实现: 分别找出以当前节点为根节点的左子树和右子树的高度并对比,如果相等,则说明是满二叉树,直接返回节点个数,如…
/* 满二叉树的特点是2^n-1,对于完全二叉树,一个node如果左右子树深度相同,那么 是一个满二叉树.如果不是,那就把node算上,继续往下看,下边的可能是满二叉树 由于完全二叉树中有一些子满二叉树,所以可以省时间 */ public int countNodes(TreeNode root) { if (root==null) return 0; int l = getLeft(root); int r = getRight(root); return (l == r)?(1<<l)-1…
完全二叉树的定义:若设二叉树的深度为h,除第 h 层外,其它各层 (1-h-1) 的结点数都达到最大个数,第 h 层所有的结点都连续集中在最左边,这就是完全二叉树. 解题思路:将树按照层进行遍历,如果出现null后还出现非null则能证明这个不是完全二叉树 https://leetcode.com/problems/check-completeness-of-a-binary-tree/discuss/205768/Java-easy-Level-Order-Traversal-one-whil…
[LeetCode]222. Count Complete Tree Nodes 解题报告(Python) 标签(空格分隔): LeetCode 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.me/ 题目地址:https://leetcode.com/problems/count-complete-tree-nodes/description/ 题目描述: Given a complete binary tree, count the n…
Count Complete Tree Nodes Given a complete binary tree, count the number of nodes. Note: Definition of a complete binary tree from Wikipedia: In a complete binary tree every level, except possibly the last, is completely filled, and all nodes in the…
Given a complete binary tree, count the number of nodes. Note: Definition of a complete binary tree from Wikipedia:In a complete binary tree every level, except possibly the last, is completely filled, and all nodes in the last level are as far left…
Given a complete binary tree, count the number of nodes. Definition of a complete binary tree from Wikipedia:In a complete binary tree every level, except possibly the last, is completely filled, and all nodes in the last level are as far left as pos…
Given the root of a complete binary tree, return the number of the nodes in the tree. According to Wikipedia, every level, except possibly the last, is completely filled in a complete binary tree, and all nodes in the last level are as far left as po…
完全二叉树是从左边开始一点点填充节点的,因此需要计算所有的节点的个数. 则分别从左边和右边来进行传递的,当左右是完全二叉树的时候,其节点个数就是pow(2,h)-1. /** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x), left(NULL), right(NULL) {} *…
Given a complete binary tree, count the number of nodes. Definition of a complete binary tree from Wikipedia: In a complete binary tree every level, except possibly the last, is completely filled, and all nodes in the last level are as far left as po…