【[leetcode]109. Convert Sorted List to Binary Search Tree链表构建二叉搜索树】的更多相关文章

[leetcode]109. Convert Sorted List to Binary Search Tree链表构建二叉搜索树

二叉树的各种遍历方式都是可以建立二叉树的,例如中序遍历,就是在第一步建立左子树,中间第二步建立新的节点,第三步构建右子树 此题利用二叉搜索树的中序遍历是递增序列的特点,而链表正好就是递增序列,从左子树开始递归利用链表的数据 控制平衡是用的递归层数,用left和right来控制 /* 各序遍历也可以建立树 利用二叉搜索树的特点,用中序遍历建立二叉树 */ //要递归listnode,所以要用全局变量 ListNode node; public TreeNode sortedListToBST(Li…

[LeetCode] 109. Convert Sorted List to Binary Search Tree 把有序链表转成二叉搜索树

Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST. 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 diffe…

Leetcode#109 Convert Sorted List to Binary Search Tree

原题地址 跟Convert Sorted Array to Binary Search Tree(参见这篇文章)类似,只不过用list就不能随机访问了. 代码: TreeNode *buildBST(ListNode *head, int len) { ) return NULL; ListNode *p = head; ; < len) { p = p->next; leftLen++; } TreeNode *node = new TreeNode(p->val); node->…

leetcode 109 Convert Sorted List to Binary Search Tree ----- java

Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST.   和上一题类似,把数组换成链表,所以可以两种做法: 1.把链表换成数组,然后用上一题的方法,这样会比较慢. 2.每次找到中间的点,作为节点,然后递归,其实原理还是二分查找.   /** * Definition for singly-linked list. * public…

Java for LeetCode 109 Convert Sorted List to Binary Search Tree

Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST. 解题思路: 同上题,JAVA实现如下: public TreeNode sortedListToBST(ListNode head) { ArrayList<Integer> list=new ArrayList<Integer>(); while(head!=nu…

[LeetCode] 108. Convert Sorted Array to Binary Search Tree 把有序数组转成二叉搜索树

Given an array where elements are sorted in ascending order, convert it to a height balanced BST. 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 th…

【LeetCode】109. Convert Sorted List to Binary Search Tree 解题报告（Python）

[LeetCode]109. Convert Sorted List to Binary Search Tree 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/convert-sorted-list-to-binary-search-tree/description/ 题目描述: Given a s…

leetcode 108. Convert Sorted Array to Binary Search Tree 、109. Convert Sorted List to Binary Search Tree

108. Convert Sorted Array to Binary Search Tree 这个题使用二分查找,主要要注意边界条件. 如果left > right,就返回NULL.每次更新的时候是mid-1,mid+1. 自己推一下基本就可以验证了. class Solution { public: TreeNode* sortedArrayToBST(vector<int>& nums) { ,nums.size() - ); } TreeNode* ToBST(vecto…

108. Convert Sorted Array to Binary Search Tree 109. Convert Sorted List to Binary Search Tree -- 将有序数组或有序链表转成平衡二叉排序树

108. Convert Sorted Array to Binary Search Tree Given an array where elements are sorted in ascending order, convert it to a height balanced BST. /** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * TreeNode *ri…

【一天一道LeetCode】#109. Convert Sorted List to Binary Search Tree

一天一道LeetCode 本系列文章已全部上传至我的github,地址:ZeeCoder's Github 欢迎大家关注我的新浪微博,我的新浪微博 欢迎转载,转载请注明出处 (一)题目 Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST. (二)解题 本题大意:给定一个单向链表,构造出平衡二叉搜索树 解题思路:参考[一天一道Leet…

[Leetcode][JAVA] Convert Sorted Array to Binary Search Tree && Convert Sorted List to Binary Search Tree

Convert Sorted Array to Binary Search Tree Given an array where elements are sorted in ascending order, convert it to a height balanced BST. 很简单的二分法,只要给出Array的开始和结束下标作为参数传入即可. public TreeNode sortedArrayToBST(int[] num) { return constructBST(num,0,nu…

【leetcode】Convert Sorted List to Binary Search Tree

Convert Sorted List to Binary Search Tree Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST.     可以采用类似于Covert Sorted Array to Binary Search Tree的方法,但是寻找中点对于链表来说效率较低 可以采用更高效的递归方式,无需寻找中点 注意引用传…

【leetcode】Convert Sorted Array to Binary Search Tree

Convert Sorted Array to Binary Search Tree Given an array where elements are sorted in ascending order, convert it to a height balanced BST.   每次把中间元素当成根节点,递归即可   /** * Definition for binary tree * struct TreeNode { * int val; * TreeNode *left; * Tre…

leetcode -day19 Convert Sorted List to Binary Search Tree

1.  Convert Sorted List to Binary Search Tree Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST. 分析:将一个升序排列的链表转换为平衡二叉搜索树,採用递归的方式,先找到链表的中点,作为二叉树的根,然后递归求解左右子树. 例如以下: class Solution { public:…

37. leetcode 108. Convert Sorted Array to Binary Search Tree

108. Convert Sorted Array to Binary Search Tree 思路:利用一个有序数组构建一个平衡二叉排序树.直接递归构建,取中间的元素为根节点,然后分别构建左子树和右子树.…

[LeetCode] 108. Convert Sorted Array to Binary Search Tree ☆(升序数组转换成一个平衡二叉树)

108. Convert Sorted Array to Binary Search Tree 描述 Given an array where elements are sorted in ascending order, convert it to a height balanced BST. For this problem, a height-balanced binary tree is defined as a binary tree in which the depth of the…

LeetCode 108. Convert Sorted Array to Binary Search Tree （将有序数组转换成BST）

108. Convert Sorted Array to Binary Search Tree Given an array where elements are sorted in ascending order, convert it to a height balanced BST. For this problem, a height-balanced binary tree is defined as a binary tree in which the depth of the tw…

LeetCode 108. Convert Sorted Array to Binary Search Tree （有序数组转化为二叉搜索树）

Given an array where elements are sorted in ascending order, convert it to a height balanced BST. 题目标签:Tree 这道题目给了我们一个有序数组,从小到大.让我们把这个数组转化为height balanced BST. 首先来看一下什么是binary search tree: 每一个点的left < 节点 < right, 换一句话说,每一个点的值要大于左边的,小于右边的. 那么什么是heigh…

leetcode 【 Convert Sorted List to Binary Search Tree 】python 实现

题目: Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST. 代码:oj测试通过 Runtime: 178 ms # Definition for a binary tree node # class TreeNode: # def __init__(self, x): # self.val = x # self.left = No…

[LeetCode 题解]:Convert Sorted List to Binary Search Tree

Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST. 题意:给定一个有序的链表,将其转换成平衡二叉搜索树 思路: 二分法 要构建一个平衡二叉树,二分法无疑是合适的,至于如何分是的代码简洁,就需要用到递归了. class Solution { public: // find middle element of the list Lis…

LeetCode OJ——Convert Sorted Array to Binary Search Tree

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LeetCode 501. Find Mode in Binary Search Tree （找到二叉搜索树的众数）

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LeetCode OJ：Validate Binary Search Tree（合法的二叉搜索树）

Given a binary tree, determine if it is a valid binary search tree (BST). Assume a BST is defined as follows: The left subtree of a node contains only nodes with keys less than the node's key. The right subtree of a node contains only nodes with keys…

LeetCode第[98]题(Java)：Validate Binary Search Tree（验证二叉搜索树）

题目:验证二叉搜索树 难度:Medium 题目内容: Given a binary tree, determine if it is a valid binary search tree (BST). Assume a BST is defined as follows: The left subtree of a node contains only nodes with keys less than the node's key. The right subtree of a node co…

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Two elements of a binary search tree (BST) are swapped by mistake. Recover the tree without changing its structure. 首先是O(N)空间的方法,用递归: /** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeN…

LeetCode OJ：Binary Search Tree Iterator（二叉搜索树迭代器）

Implement an iterator over a binary search tree (BST). Your iterator will be initialized with the root node of a BST. Calling next() will return the next smallest number in the BST Note: next() and hasNext() should run in average O(1) time and uses O…

[LeetCode] 98. Validate Binary Search Tree(是否是二叉搜索树) ☆☆☆

描述 解析 二叉搜索树,其实就是节点n的左孩子所在的树,每个节点都小于节点n. 节点n的右孩子所在的树,每个节点都大于节点n. 定义子树的最大最小值 比如:左孩子要小于父节点:左孩子n的右孩子要大于n的父节点.以此类推. 中序遍历 中序遍历时,输出的值,和前一个值比较,如果大,就失败. 代码 /** * Definition for a binary tree node. * public class TreeNode { * int val; * TreeNode left; * TreeNo…

【leetcode】Convert Sorted Array to Binary Search Tree (easy)

Given an array where elements are sorted in ascending order, convert it to a height balanced BST. 有序数组变二叉平衡搜索树,不难,递归就行.每次先序建立根节点(取最中间的数),然后用子区间划分左右子树. 一次就AC了 注意:new 结构体的时候对于 struct TreeNode { int val; TreeNode *left; TreeNode *right; TreeNode(int x)…

【Leetcode】109. Convert Sorted List to Binary Search Tree

Question: Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST. 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 n…

LeetCode OJ 109. Convert Sorted List to Binary Search Tree

Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST. 涉及到二叉树的问题用递归的方法很容易理解.这个问题要求把一个升序排序的链表转换为一颗height balanced BST.转换的方式就是把链表的中间值作为树的根节点,中间值的左半部分转换为二叉树的左子树,中间值的右半部分转换为二叉树的右子树. 递归解决问题的步骤如下: 1. 如…