inorder,(long)Integer.MAX_VALUE+1);}intpre=0;intin=0;privateTreeNodebuildTreeHelper(int[]preorder,int[]inorder,longstop){//到达末尾返回 nullif(pre==preorder.length){returnnull;}//到达停止点返回 null//当前停止点已经用了,in 后
root.right= self.buildTree(preorder[i+1:], inorder[i+1:])returnroot 同样的方法做106. Construct Binary Tree from Inorder and Postorder Traversal,后序和中序,建二叉树,根节点是后序的最后一个元素。 classSolution(object):defbuildTree(self, inorder, postorder):""":type inorder: List[int] ...
}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...
比如对于本题而言,buildTree(preorder, inorder)函数的输入是一棵树的先序遍历序列和中序遍历序列,该函数的返回值是构建好的这棵树的根节点。我们在找到root节点后,设定其左右子树时,依然调用buildTree(preorder, inorder),此时的输入变成了root左右子树对应的先序遍历和中序遍历序列,该函数的返回值就是构建好的...
Given preorder and inorder traversal of a tree, construct the binary tree. 本题就是根据前序遍历和中序遍历的结果还原一个二叉树。 题意很简答,就是递归实现,直接参考代码吧。 查询index部分可以使用Map做查询,建议和下一道题 leetcode 106. Construct Binary Tree from Inorder and Postorder Traversal 中...
5. Construct Binary Tree from Preorder and Inorder Traversal 与上题类似,我们知道preorder第一个元素一定是根节点,按照这个特性可以找出根节点在inorder中的位置,从该位置分开,左右两边分别就是左右子树。 class Solution: def buildTree(self, preorder: List[int], inorder: List[int]) -> TreeNode: if...
Can you solve this real interview question? Binary Tree Preorder Traversal - Given the root of a binary tree, return the preorder traversal of its nodes' values. Example 1: Input: root = [1,null,2,3] Output: [1,2,3] Explanation: [https://assets.l
Unfortunately, the .NET Framework does not contain a binary tree class, so in order to better understand binary trees, let's take a moment to create our own binary tree class. The First Step: Creating a Base Node Class The first step in designing our binary tree class is to create a ...
Unfortunately, the .NET Framework does not contain a binary tree class, so in order to better understand binary trees, let's take a moment to create our own binary tree class. The First Step: Creating a Base Node Class The first step in designing our binary tree class is to create a ...
题目:105. 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. 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。