LeetCode:Convert Sorted Array to Binary Search Tree Given an array where elements are sorted in ascending order, convert it to a height balanced BST 分析:找到数组的中间数据作为根节点,小于中间数据的数组来构造作为左子树,大于中间数据的数组来构造右子树,递归解法如下 /** * Definition for binary tree * struct…
Convert Sorted Array to Binary Search Tree Given an array where elements are sorted in ascending order, convert it to a height balanced BST.SOLUTION 1:使用递归解决. base case: 当索引值超过时,返回null. 递归主体:构造根节点,调用递归构造左右子树.并将左右子树挂在根节点上. 返回值:返回构造的根节点. GITHUB: https:…
Given an array where elements are sorted in ascending order, convert it to a height balanced BST. 这道题是要将有序数组转为二叉搜索树,所谓二叉搜索树,是一种始终满足左<根<右的特性,如果将二叉搜索树按中序遍历的话,得到的就是一个有序数组了.那么反过来,我们可以得知,根节点应该是有序数组的中间点,从中间点分开为左右两个有序数组,在分别找出其中间点作为原中间点的左右两个子节点,这不就是是二分查找法的核…
Description: Given an array where elements are sorted in ascending order, convert it to a height balanced BST. 给一个升序有序的数组,构建一个平衡的二叉查找树. 要平衡就要找中间的数来做头结点,递归构造. /** * Definition for a binary tree node. * public class TreeNode { * int val; * TreeNode lef…
题目: Given an array where elements are sorted in ascending order, convert it to a height balanced BST. 思路: 总是取中间点为root package bst; public class ConvertSortedArrayToBinarySearchTree { public TreeNode sortedArrayToBST(int[] nums) { return constructBST(…
原题地址:http://oj.leetcode.com/problems/convert-sorted-array-to-binary-search-tree/ 题意:将一个排序好的数组转换为一颗二叉查找树,这颗二叉查找树要求是平衡的. 解题思路:由于要求二叉查找树是平衡的.所以我们可以选在数组的中间那个数当树根root,然后这个数左边的数组为左子树,右边的数组为右子树,分别递归产生左右子树就可以了. 代码: # Definition for a binary tree node # class…
题意: 将一个有序的数组建成一棵平衡的BST树. 思路: 因为数组已经有序,每次可以从中点开始建根,再递归下去分别处理左/右子树. /** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x), left(NULL), right(NULL) {} * }; */ class Soluti…
Problem Link: http://oj.leetcode.com/problems/convert-sorted-array-to-binary-search-tree/ Same idea to Convert Sorted Array to Binary Search Tree, but we use a recursive function to construct the binary search tree. # Definition for a binary tree nod…
108. 将有序数组转换为二叉搜索树 108. Convert Sorted Array to Binary Search Tree 题目描述 将一个按照升序排列的有序数组,转换为一棵高度平衡二叉搜索树. 本题中,一个高度平衡二叉树是指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2019/5/17Day 14LeetCode108. Convert Sorted Array to Binary Search Tree 示例: 给定有序数组: [-10,-3,0,5,9…
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…