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…

解法一:递归 int countNodes(TreeNode* root) { if (root == NULL) ; TreeNode *pLeft = root->left; TreeNode *pRight = root->right; , rdepth = ; while (pLeft) { ldepth++; pLeft = pLeft->left; } while (pRight) { rdepth++; pRight = pRight->right; } if (ld…

1 题目 Given a complete binary tree, count the number of nodes. 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 possible. It can have between 1 and 2h nodes inclu…

[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…

2018-09-25 16:36:25 问题描述: 问题求解: 单纯遍历了一遍,emmm,果然TLE. 解题思路就是比较左边树高度和右边树高度,如果相等,那么就是一个满二叉树,返回1 << h - 1即可,如果不是,则递归的计算左右子树的个数. 时间复杂度:O(logn * logn) public int countNodes(TreeNode root) { if (root == null) return 0; int l = leftHeight(root); int r = righ…

原题链接在这里:https://leetcode.com/problems/count-complete-tree-nodes/ 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 complete…

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…

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…

题目描述 给出一个完全二叉树,求出该树的节点个数. 说明: 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. 示例: 输入: 1 / \ 2 3 / \ / 4 5 6 输出: 6 解题思路 从根节点开始分别判断左右子树的高度: 若左子树高度等于右子树,说明左子树一定为满二叉树,可得左子树的总节点个数,然后递归求右子树的节点数: 若左子树高度大于右…

/* 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…

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…

Description: Given a complete binary tree, count the number of nodes. 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 possible. It can have between 1 and 2hnode…

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…

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 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…

Total Accepted: 32628 Total Submissions: 129569 Difficulty: Medium 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 comple…

Question: 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…

题意 给一棵 complete binary tree,数数看一共有多少个结点.做题链接 直观做法:递归 var countNodes = function(root) { if(root===null) return 0; return 1+countNodes(root.left)+countNodes(root.right); }; 老实说,一道难度为 medium 的题目,这么几秒钟的时间就做出来,我心中有一种不真实感. 所以,我看了一下 discuss 区其他人的解法,看是不是我自己想…

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…

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…

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) {} *…

/** * Definition for a binary tree node. * struct TreeNode { * int val; * struct TreeNode *left; * struct TreeNode *right; * }; */ #define MAX 1000 int Path[MAX]; int index1; int power(int x,int n){ int i,re; if(n==0)return 1; for(i=0,re=1;i<n;++i){…

解法一:非递归 vector<int> preorderTraversal(TreeNode* root) { vector<int> res; if (root == NULL) return res; stack<TreeNode*> node_stack; TreeNode *p = root; while (p || !node_stack.empty()) { if (p) { res.push_back(p->val); node_stack.push…

解法一:递归 bool isSameTree(TreeNode* p, TreeNode* q) { if (p == NULL && q == NULL) return true; if ((p == NULL && q != NULL) || (p != NULL && q == NULL)) return false; if (p->val != q->val) return false; if (!isSameTree(p->lef…

题目: 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…

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…