TreeNode root = buildHelper(preorder,0, len -1, inorder,0, len -1); returnroot; } privateTreeNode buildHelper(int[] preorder,intpre_start,intpre_end, int[] inorder,intin_start,intin_end) { // bound if(pre_start > pre_end || in_start > in_end) { returnnull; } introotVa...
}privateTreeNode buildTree(int[] preorder,intpreLo,intpreHi,int[] inorder,intinLo,intinHi) {if(preLo > preHi || inLo > inHi)returnnull;introotVal =preorder[preLo]; TreeNode root=newTreeNode(rootVal);introotIndexAtInorder =inLo;while(rootIndexAtInorder <=inHi) {if(inorder[rootIn...
public TreeNode buildTree(int[] preorder, int[] inorder) { if(preorder==null || inorder==null) return null; HashMap<Integer, Integer> map = new HashMap<Integer, Integer>(); for(int i=0;i<inorder.length;i++) { map.put(inorder[i],i); } return helper(preorder,0,preorder.l...
题目地址:https://leetcode.com/problems/construct-binary-tree-from-preorder-and-inorder-traversal/description/ 题目描述 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...
Construct Binary Tree from Preorder and Inorder Traversal 题目描述(中等难度) 根据二叉树的先序遍历和中序遍历还原二叉树。 解法一 递归 先序遍历的顺序是根节点,左子树,右子树。中序遍历的顺序是左子树,根节点,右子树。 所以我们只需要根据先序遍历得到根节点,然后在中序遍历中找到根节点的位置,它的左边就...
15、课程:树(下).10、练习—Iterative Postorder Traversal -- -- 10:33 App 15、课程:树(下).7、练习—Iterative Get和Iterative Add 2 -- 12:36 App 15、课程:树(下).13、练习—Construct Binary Tree from Preorder and Inorder Traversal 1 -- 9:07 App 15、课程:树(下).3、练习—Floor and...
INORDER AND PREORDER TRAVERSAL and DISPLAY OF EXISTING BINARY TREE IN COMPUTER MEMORYP K KumaresanJournal of Harmonized Research
Given preorder and inorder traversal of a tree, construct the binary tree. Note: You may assume that duplicates do not exist in the tree. 翻译:给定树的前序和中序遍历,构造二叉树。 注意: 树中不存在重复项。 思路:首先,你应该知道 前序遍历:根节点,左子树,右子树; ...
* TreeNode right; * TreeNode(int x) { val = x; } * } */publicclassSolution{public TreeNodebuildTree(int[]preorder,int[]inorder){if(preorder==null||preorder.length==0)returnnull;if(inorder==null||inorder.length==0)returnnull;if(preorder.length!=inorder.length)returnnull;returnbui...
Binary tree traversal: Preorder, Inorder, and Postorder In order to illustrate few of the binary tree traversals, let us consider the below binary tree: Preorder traversal: To traverse a binary tree in Preorder, following operations are carried-out (i) Visit the root, (ii) Traverse the le...