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…

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…

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…

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…

Given preorder and inorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. For example, given preorder = [3,9,20,15,7] inorder = [9,3,15,20,7] Return the following binary tree: 3 / \ 9 20…

Given preorder and inorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. For example, given preorder = [3,9,20,15,7] inorder = [9,3,15,20,7] Return the following binary tree: 3 / \ 9 20…

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…

Given preorder and inorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. 题目标签:Array, Tree 题目给了我们preOrder 和 inOrder 两个遍历array,让我们建立二叉树.先来举一个例子,让我们看一下preOrder 和 inOrder的特性. / \   /      \…

Given preorder and inorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. 给出前序遍历和中序遍历,然后求这棵树. 很有规律.递归就可以实现. /** * Definition for a binary tree node. * public class TreeNode { * int val; *…