1.题目 2.思路 3.java代码 //测试 public class BuildTreeUsingInorderAndPreorder { public static void main(String[] args) { int[] preSort={1,2,4,7,3,5,6,8}; int[] inSort={4,7,2,1,5,3,8,6}; System.out.println(new Solution().buildTree(preSort, inSort)); } } //利用前…

题目: Given preorder and inorder traversal of a tree, construct the binary tree. 思路: 线序序列的第一个元素就是树根,然后在中序序列中找到这个元素(由于题目保证没有相同的元素,因此可以唯一找到),中序序列中这个元素的左边就是左子树的中序,右边就是右子树的中序,然后根据刚才中序序列中左右子树的元素个数可以在后序序列中找到左右子树的后序序列,然后递归的求解即可. /** * Definition for a binary…

Given preorder and inorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. 解题思路: 给出一个二叉树的先序和中序遍历结果,还原这个二叉树. 对于一个二叉树: 1 / \ 2 3 / \ / \ 4 5 6 7 先序遍历结果为:1 2 4 5 3 6 7 中序遍历结果为:4 2 5 1 6 3 7 由…

Given preorder and inorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. public class Solution { public TreeNode buildTree(int[] preorder, int[] inorder) { if(preorder.length==0||inorder…

Problem Link: https://oj.leetcode.com/problems/construct-binary-tree-from-preorder-and-inorder-traversal/ The basic idea is same to that for Construct Binary Tree from Inorder and Postorder Traversal. We solve it using a recursive function. First, we…

Given preorder and inorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. 类似http://www.cnblogs.com/sunshineatnoon/p/3854935.html 只是子树的前序和中序遍历序列分别更新为: //左子树: left_prestart = prestart+1 lef…

题目: Given preorder and inorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. 解题思路分析: 前序遍历首先遍历根节点,然后依次遍历左右子树 中序遍历首先遍历左子树,然后遍历根结点,最后遍历右子树 根据二者的特点,前序遍历的首节点就是根结点,然后在中序序列中找出该结点位置(index),则该结点之…

LeetCode 原题链接 Construct Binary Tree from Inorder and Postorder Traversal - LeetCode Construct Binary Tree from Preorder and Postorder Traversal - LeetCode 题目大意 给定一棵二叉树的中序遍历和后序遍历,求这棵二叉树的结构. 给定一棵二叉树的前序遍历和中序遍历,求这棵二叉树的结构. 样例 Input: inorder = [9, 3, 15, 2…

Construct Binary Tree from Preorder and Inorder Traversal Given preorder and inorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. 可与Construct Binary Tree from Inorder and Postorder Trav…

LeetCode:Construct Binary Tree from Inorder and Postorder Traversal Given inorder and postorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree.                                            …