题解 挺水的一道题. Rating $ \color{orange} {2300}$ 以下送命题. 首先我们知道,所有子树大小之和就是节点个数加上从根到所有节点的路径长度之和. 他要求度数尽可能小,所以我们二分度数\(k\).显然,度数越小,子树和越大. 对于一个\(k\)叉树,他的子树大小之和为\(n+k^2+k^3+...+rem\) 我们通过二分得到最大的边界\(k\) 然后,此时我们的子树大小\(s\)是要小于等于规定的子树大小和的. 我们考虑扩大子树大小. 显然,我们让某些节点,往深度…

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…

Sept. 13, 2015 Spent more than a few hours to work on the leetcode problem, and my favorite blogs about this problems: 1. http://siddontang.gitbooks.io/leetcode-solution/content/tree/construct_binary_tree.html 2.http://blog.csdn.net/linhuanmars/artic…

题目: Given inorder and postorder traversal of a tree, construct the binary tree. Note: You may assume that duplicates do not exist in the tree. 题解: 这道题跟pre+in一样的方法做,只不过找左子树右子树的位置不同而已. / \ / \ / \ 对于上图的树来说, index: 0 1 2 3 4 5 6 中序遍历为为了清晰表示,我给节点上了颜色,红色是…

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. 题解: / \ / \ / \ 对于上图的树来说, index: 0 1 2 3 4 5 6 先序遍历为                                                        …

Construct Binary Tree from Inorder and Postorder Traversal 题解 原创文章,拒绝转载 题目来源:https://leetcode.com/problems/construct-binary-tree-from-inorder-and-postorder-traversal/description/ Description Given inorder and postorder traversal of a tree, construct…

Given inorder and postorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. 题解:如下图所示的一棵树: 5 / \ 2 4 / \ \ 1 3 6 中序遍历序列:1  2  3  5  4  6 后序遍历序列:1  3  2  6  4  5 后序遍历序列的最后一个元素就是当前根节点元素.首先想到的…

原题链接在这里:https://leetcode.com/problems/construct-binary-tree-from-preorder-and-postorder-traversal/ 题目: Return any binary tree that matches the given preorder and postorder traversals. Values in the traversals pre and post are distinct positive intege…

Given preorder and inorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. 这道题要求用先序和中序遍历来建立二叉树,跟之前那道Construct Binary Tree from Inorder and Postorder Traversal 由中序和后序遍历建立二叉树原理基本相同,针对这道题,由于先…

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…