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Given inorder and postorder traversal of a tree, construct the binary tree.Note:You may assume that duplicates do not exist in the tree.For example, giveninorder =[9,3,15,20,7]postorder = [9...

Say you have an array for which theithelement is the price of a given stock on dayi.Design an algorithm to find the maximum profit. You may complete at mosttwotransactions.Note:You may not en...

Given anon-emptybinary tree, find the maximum path sum.For this problem, a path is defined as any sequence of nodes from some starting node to any node in the tree along the parent-child connectio...

Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases.Note:For the purpose of this problem, we define empty string as valid palindrome.Examp...

Given two words (beginWordandendWord), and a dictionary's word list, find the length of shortest transformation sequence frombeginWordtoendWord, such that:Only one letter can be changed at a ti...

Given an unsorted array of integers, find the length of the longest consecutive elements sequence.Your algorithm should run in O(n) complexity.Example:Input:[100, 4, 200, 1, 3, 2]Output: 4Ex...

Given a binary tree containing digits from0-9only, each root-to-leaf path could represent a number.An example is the root-to-leaf path1->2->3which represents the number123.Find the tota...

Given a 2D board containing'X'and'O'(the letter O), capture all regions surrounded by'X'.A region is captured by flipping all'O's into'X's in that surrounded region.Example:X X X XX O O...

Given a strings, partitionssuch that every substring of the partition is a palindrome.Return all possible palindrome partitioning ofs.Example:Input:"aab"Output:[ ["aa","b"], ["a","a"...

Given a strings, partitionssuch that every substring of the partition is a palindrome.Return the minimum cuts needed for a palindrome partitioning ofs.Example:Input:"aab"Output: 1Explana...

Givena reference of a node in aconnectedundirected graph, return adeep copy(clone) of the graph. Each node in the graph contains a val (int) and a list (List[Node]) of its neighbors.Example:...

There areNgas stations along a circular route, where the amount of gas at stationiisgas[i].You have a car with an unlimited gas tank and it costscost[i]of gas to travel from stationito its ...

A linked list is given such that each node contains an additional random pointer which could point to any node in the list or null.Return adeep copyof the list.Example 1:Input:{"$id":"1...

Given anon-emptystringsand a dictionarywordDictcontaining a list ofnon-emptywords, determine ifscan be segmented into a space-separated sequence of one or more dictionary words.Note:The s...

Given anon-emptystringsand a dictionarywordDictcontaining a list ofnon-emptywords, add spaces insto construct a sentence where each word is a valid dictionary word.Return all such possible s...

Given a linked list, determine if it has a cycle in it.To represent a cycle in the given linked list, we use an integerposwhich represents the position (0-indexed)in the linked list where tail co...

Given a linked list, return the node where the cycle begins. If there is no cycle, returnnull.To represent a cycle in the given linked list, we use an integerposwhich represents the position (0-i...

Say you have an array for which theithelement is the price of a given stock on dayi.Design an algorithm to find the maximum profit. You may complete as many transactions as you like (i.e., buy on...

Say you have an array for which theithelement is the price of a given stock on dayi.If you were only permitted to complete at most one transaction (i.e., buy one and sell one share of the stock),...

Given a binary tree, return thebottom-up level ordertraversal of its nodes' values. (ie, from left to right, level by level from leaf to root).For example:Given binary tree[3,9,20,null,null,15,7...

Given an array where elements are sorted in ascending order, convert it to a height balanced BST.For this problem, a height-balanced binary tree is defined as a binary tree in which the depth of the...

Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST.For this problem, a height-balanced binary tree is defined as a binary tree in which the ...

Given a binary tree, determine if it is height-balanced.For this problem, a height-balanced binary tree is defined as:a binary tree in which the depth of the two subtrees ofeverynode never diff...

Given a binary tree, find its minimum depth.The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node.Note:A leaf is a node with no childre...

Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum.Note:A leaf is a node with no children.Example:...

Given a binary tree and a sum, find all root-to-leaf paths where each path's sum equals the given sum.Note:A leaf is a node with no children.Example:Given the below binary tree andsum = 22,...

Given a binary tree, flatten it to a linked list in-place.For example, given the following tree: 1 / \ 2 5 / \ \3 4 6The flattened tree should look like:1 \ 2 \ ...

Given a stringSand a stringT, count the number of distinct subsequences ofSwhich equalsT.A subsequence of a string is a new string which is formed from the original string by deleting some (ca...

You are given aperfect binary treewhereall leaves are on the same level, and every parent has two children. The binary tree has the following definition:struct Node { int val; Node *left; ...

Given a non-negative integernumRows, generate the firstnumRowsof Pascal's triangle.In Pascal's triangle, each number is the sum of the two numbers directly above it.Example:Input: 5Output:[...

Given a non-negativeindexkwherek≤33, return thekthindex row of the Pascal's triangle.Note that the row index starts from0.In Pascal's triangle, each number is the sum of the two numbers ...

Given a triangle, find the minimum path sum from top to bottom. Each step you may move to adjacent numbers on the row below.For example, given the following triangle[ [2], [3,4], [6,5...

There areNchildren standing in a line. Each child is assigned a rating value.You are giving candies to these children subjected to the following requirements:Each child must have at least one ca...

Given anon-emptyarray of integers, every element appearstwiceexcept for one. Find that single one.Note:Your algorithm should have a linear runtime complexity. Could you implement it without us...

Given a binary treestruct Node { int val; Node *left; Node *right; Node *next;}Populate each next pointer to point to its next right node. If there is no next right node, the next point...

Given a singly linked listL:L0→L1→…→Ln-1→Ln,reorder it to:L0→Ln→L1→Ln-1→L2→Ln-2→…You maynotmodify the values in the list's nodes, only nodes itself may be changed.Example 1:Given 1->2-...