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…
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…
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->…
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…
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…
Given an array where elements are sorted in ascending order, convert it to a height balanced BST. 给一个排好序的数组,然后求搜索二叉树 其实就是二分法,不难. /** * Definition for a binary tree node. * public class TreeNode { * int val; * TreeNode left; * TreeNode right; * TreeNo…
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) 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…
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 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…