CJOJ 1976 二叉苹果树 / URAL 1018 Binary Apple Tree(树型动态规划) Description 有一棵苹果树,如果树枝有分叉,一定是分2叉(就是说没有只有1个儿子的结点)这棵树共有N个结点(叶子点或者树枝分叉点),编号为1-N,树根编号一定是1.我们用一根树枝两端连接的结点的编号来描述一根树枝的位置.现在这颗树枝条太多了,需要剪枝.但是一些树枝上长有苹果. 给定需要保留的树枝数量,求出最多能留住多少苹果.下面是一颗有 4 个树枝的树. 2 5 \ / 3 4…

Let's imagine how apple tree looks in binary computer world. You're right, it looks just like a binary tree, i.e. any biparous branch splits up to exactly two new branches. We will enumerate by integers the root of binary apple tree, points of branch…

题目链接:http://acm.timus.ru/problem.aspx?space=1&num=1018 Dynamic Programming. 首先要根据input建立树形结构,然后在用DP来寻找最佳结果.dp[i][j]表示node i的子树上最多保存j个分支的最佳结果.代码如下: #include <iostream> #include <math.h> #include <stdio.h> #include <cstdio> #incl…

本文出自   http://blog.csdn.net/shuangde800 --------------------------------------------------------------------------------- 题目链接:  url-1018 题意 给一棵边有权值的二叉树,节点编号为1-n,1是根节点.求砍掉一些边,只保留q条边,这q条边构成的子树    的根节点要求是1,问这颗子树的最大权值是多少? 思路 非常经典的一道树形dp题,根据我目前做过的题来看,有多道…

1018. Binary Apple Tree Time limit: 1.0 secondMemory limit: 64 MB Let's imagine how apple tree looks in binary computer world. You're right, it looks just like a binary tree, i.e. any biparous branch splits up to exactly two new branches. We will enu…

POJ 2342 Anniversary party / HDU 1520 Anniversary party / URAL 1039 Anniversary party(树型动态规划) Description There is going to be a party to celebrate the 80-th Anniversary of the Ural State University. The University has a hierarchical structure of emp…

[本文链接] http://www.cnblogs.com/hellogiser/p/array-to-binary-search-tree.html [题目] 编写一个程序,把一个有序整数数组放到二叉搜索树中. 例如 4,6,8,10,12,14,16 转换为二叉搜索树为 10 / \ 6    14 / \    /  \ 4   8 12   16 [分析] 按照中序遍历的方法转换到二叉搜索树中.先要确定一个根节点,然后递归创建左右子树. [代码]  C++ Code  123456789…

Given a binary search tree and the lowest and highest boundaries as L and R, trim the tree so that all its elements lies in [L, R] (R >= L). You might need to change the root of the tree, so the result should return the new root of the trimmed binary…

开一个指针数组,中序遍历这个二叉搜索树,将节点的指针依次保存在数组里, 然后寻找两处逆序的位置, 中序便利里BST得到的是升序序列 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 二叉搜索树(BST)中的两个节点不小心被交换了下. 不改变其结构的情况下恢复这个树. 笔记: 用O(n)的空间复杂度的方法很直接.你能否设计一个常量空间的解决法方案? +++++++++++++++++…

669. 修剪二叉搜索树 669. Trim a Binary Search Tree 题目描述 LeetCode LeetCode669. Trim a Binary Search Tree简单 Java 实现 TreeNode Class public class TreeNode { int val; TreeNode left; TreeNode right; TreeNode(int x) { val = x; } } class Solution { public TreeNode…