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…
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…
Binary Apple Tree Time Limit: 1000ms Memory Limit: 16384KB This problem will be judged on Ural. Original ID: 101864-bit integer IO format: %lld Java class name: (Any) Let's imagine how apple tree looks in binary computer world. You're right,…
#include<cstdio> #include<cstring> #include<iostream> #include<algorithm> #include<vector> using namespace std; ; int dp[maxn][maxn]; //dp[i][j]表示以i为根,保留j个点的最大权值. int N,Q; int G[maxn][maxn]; int num[maxn]; //以i为根的树的节点个数. //这里…
题目链接:Recover Binary Search Tree | LeetCode OJ Two elements of a binary search tree (BST) are swapped by mistake. Recover the tree without changing its structure. Note: A solution using O(n) space is pretty straight forward. Could you devise a constan…
题目链接:Validate Binary Search Tree | LeetCode OJ Given a binary tree, determine if it is a valid binary search tree (BST). Assume a BST is defined as follows: The left subtree of a node contains only nodes with keys less than the node's key. The right…
Sept. 22, 2015 学一道算法题, 经常回顾一下. 第二次重温, 决定增加一些图片, 帮助自己记忆. 在网上找他人的资料, 不如自己动手. 把从底向上树的算法搞通俗一些. 先做一个例子: 9/22/2015 Go over one example to build some muscle memory about this bottom up, O(1) solution to find the root node in subtree function. Sorted List: 1…
Given a non-empty binary search tree and a target value, find k values in the BST that are closest to the target. Note: Given target value is a floating point. You may assume k is always valid, that is: k ≤ total nodes. You are guaranteed to have onl…
Given a non-empty binary search tree and a target value, find the value in the BST that is closest to the target. Note: Given target value is a floating point. You are guaranteed to have only one unique value in the BST that is closest to the target.…
Given an array of numbers, verify whether it is the correct preorder traversal sequence of a binary search tree. You may assume each number in the sequence is unique. Follow up: Could you do it using only constant space complexity? 这道题让给了我们一个一维数组,让我们…
Given a binary search tree (BST), find the lowest common ancestor (LCA) of two given nodes in the BST. According to the definition of LCA on Wikipedia: “The lowest common ancestor is defined between two nodes v and w as the lowest node in T that has…
Implement an iterator over a binary search tree (BST). Your iterator will be initialized with the root node of a BST. Calling next() will return the next smallest number in the BST. Note: next() and hasNext() should run in average O(1) time and uses…
Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST. 这道题是要求把有序链表转为二叉搜索树,和之前那道Convert Sorted Array to Binary Search Tree 将有序数组转为二叉搜索树思路完全一样,只不过是操作的数据类型有所差别,一个是数组,一个是链表.数组方便就方便在可以通过index直接访问任意一个元…
Given an array where elements are sorted in ascending order, convert it to a height balanced BST. 这道题是要将有序数组转为二叉搜索树,所谓二叉搜索树,是一种始终满足左<根<右的特性,如果将二叉搜索树按中序遍历的话,得到的就是一个有序数组了.那么反过来,我们可以得知,根节点应该是有序数组的中间点,从中间点分开为左右两个有序数组,在分别找出其中间点作为原中间点的左右两个子节点,这不就是是二分查找法的核…
Two elements of a binary search tree (BST) are swapped by mistake. Recover the tree without changing its structure. Note:A solution using O(n) space is pretty straight forward. Could you devise a constant space solution? confused what "{1,#,2,3}"…
Given a binary tree, determine if it is a valid binary search tree (BST). Assume a BST is defined as follows: The left subtree of a node contains only nodes with keys less than the node's key. The right subtree of a node contains only nodes with keys…
Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST. Top down 的解题方法: 1. 将LinkedList的值保存到一个数组中,转化成Convert Sorted Array to Binary Search Tree 来解决 时间复杂度为O(n), 空间复杂度为O(n) /** * Definition for singl…
验证一个list是不是一个BST的preorder traversal sequence. Given an array of numbers, verify whether it is the correct preorder traversal sequence of a binary search tree. You may assume each number in the sequence is unique. Follow up:Could you do it using only…
Given a binary search tree (BST), find the lowest common ancestor (LCA) of two given nodes in the BST. According to the definition of LCA on Wikipedia: “The lowest common ancestor is defined between two nodes v and w as the lowest node in T that has…
原题链接在这里:https://leetcode.com/problems/verify-preorder-sequence-in-binary-search-tree/ 题目: Given an array of numbers, verify whether it is the correct preorder traversal sequence of a binary search tree. You may assume each number in the sequence is u…
1064. Complete Binary Search Tree (30) 时间限制 100 ms 内存限制 32000 kB 代码长度限制 16000 B 判题程序 Standard 作者 CHEN, Yue A Binary Search Tree (BST) is recursively defined as a binary tree which has the following properties: The left subtree of a node contains only…