wyxwyx469410930的博客

学习目标：1. 希尔排序2. 洗牌算法3. 葛立恒扫描法

leetcode 130.Surrounded Regions题目：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 surrounde...

leetcode 494. Target Sum题目：You are given a list of non-negative integers, a1, a2, …, an, and a target, S. Now you have 2 symbols + and -. For each integer, you should choose one from + and - as its ...

leetcode 134. Gas Station题目：There are N gas stations along a circular route, where the amount of gas at station i is gas[i].You have a car with an unlimited gas tank and it costs cost[i] of gas to ...

leetcode 113. Path Sum II题目：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 b...

leetcode 105. Construct Binary Tree from Preorder and Inorder Traversal题目：Given preorder and inorder traversal of a tree, construct the binary tree.Note:You may assume that duplicates do not exist...

leetcode 365. Water and Jug Problem题目：You are given two jugs with capacities x and y litres. There is an infinite amount of water supply available. You need to determine whether it is possible to me...

leetcode 55. Jump Game题目：Given an array of non-negative integers, you are initially positioned at the first index of the array.Each element in the array represents your maximum jump length at that ...

leetcode 79.Word Search题目:Given a 2D board and a word, find if the word exists in the grid.The word can be constructed from letters of sequentially adjacent cell, where “adjacent” cells are those h...

leetcode 300. Longest Increasing Subsequence题目：Given an unsorted array of integers, find the length of longest increasing subsequence.Example:Input: [10,9,2,5,3,7,101,18]Output: 4 Explanation: T...

LeetCode 441. Arranging Coins题目：You have a total of n coins that you want to form in a staircase shape, where every k-th row must have exactly k coins.Given n, find the total number of full stairca...

leetcode 343. Integer Break题目：Given a positive integer n, break it into the sum of at least two positive integers and maximize the product of those integers. Return the maximum product you can get....

leetcode 846. Hand of Straights题目：Alice has a hand of cards, given as an array of integers.Now she wants to rearrange the cards into groups so that each group is size W, and consists of W consecuti...

leetcode 837. New 21 Game题目：Alice plays the following game, loosely based on the card game “21”.Alice starts with 0 points, and draws numbers while she has less than K points. During each draw, sh...

leetcode 179. Largest Number题目：Given a list of non negative integers, arrange them such that they form the largest number.Example 1:Input: [10,2]Output: "210"Example 2:Input: [3,30,34,5,9]Out...

leetcode 606. Construct String from Binary Tree题目：You need to construct a string consists of parenthesis and integers from a binary tree with the preorder traversing way.The null node needs to be r...

leetcode 881. Boats to Save People题目：The i-th person has weight people[i], and each boat can carry a maximum weight of limit.Each boat carries at most 2 people at the same time, provided the sum of...

leetcode 98.Validate Binary Search Tree题目：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 nod...

leetcode 466. Count The Repetitions题目：Define S = [s,n] as the string S which consists of n connected strings s. For example, ["abc", 3] =“abcabcabc”.On the other hand, we define that string s1 can ...

leetcode 145. Binary Tree Postorder Traversal题目：Given a binary tree, return the postorder traversal of its nodes’ values.Example:Input: [1,null,2,3] 1 \ 2 / 3Output: [3,2,1]...

leetcode 444. Sequence ReconstructionCheck whether the original sequence org can be uniquely reconstructed from the sequences in seqs. The org sequence is a permutation of the integers from 1 to n, w...

Leetcode 688.Knight Probability in Chessboard题目：On an NxN chessboard, a knight starts at the r-th row and c-th column and attempts to make exactly K moves. The rows and columns are 0 indexed, so the...

Leetcode 135.Candy题目：There are N children 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 mus...

Leetcode 6. ZigZag Conversion题目：The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legib...

Leetcode 600. Non-negative Integers without Consecutive Ones题目：Given a positive integer n, find the number of non-negative integers less than or equal to n, whose binary representations do NOT conta...

Leetcode 735题目：We are given an array asteroids of integers representing asteroids in a row.For each asteroid, the absolute value represents its size, and the sign represents its direction (positive...

Leetcode 99. Recover Binary Search Tree题目：Two elements of a binary search tree (BST) are swapped by mistake.Recover the tree without changing its structure.Example 1:Input: [1,3,null,null,2] ...

Leetcode 90题目：Given a collection of integers that might contain duplicates, nums, return all possible subsets (the power set).Note: The solution set must not contain duplicate subsets.Example:Inp...

Leetcode 97. Interleaving StringGiven s1, s2, s3, find whether s3 is formed by the interleaving of s1 and s2.Example 1:Input: s1 = "aabcc", s2 = "dbbca", s3 = "aadbbcbcac"Out

leetcode 76.Minimum Window Substring题目：Given a string S and a string T, find the minimum window in S which will contain all the characters in T in complexity O(n).Example:Input: S = "ADOBECODEBANC...

leetcode 690. Employee importance题目：You are given a data structure of employee information, which includes the employee’s unique id, his importance valueand his direct subordinates’ id.For example,...

leetcode 109. Convert Sorted List to Binary Search Tree题目:Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST.For this problem, a height-bal...

leetcode 738.Monotone Increasing Digits题目：Given a non-negative integer N, find the largest number that is less than or equal to N with monotone increasing digits.(Recall that an integer has monoton...

leetcode 108. Convert Sorted Array to Binary Search Tree题目:Given an array where elements are sorted in ascending order, convert it to a height balanced BST.For this problem, a height-balanced binar...

Leetcode 84.Largest Rectangle in Histogram题目：Given n non-negative integers representing the histogram’s bar height where the width of each bar is 1, find the area of largest rectangle in the histogr...

leetcode 93.Restore IP Addresses题目：Given a string containing only digits, restore it by returning all possible valid IP address combinations.Example:Input: "25525511135"Output: ["255.255.11.135",...

Leetcode 250.Count Univalue Subtrees题目：Given a binary tree, count the number of uni-value subtrees.A Uni-value subtree means all nodes of the subtree have the same value.For example:Given binary ...

leetcode 553.Optimal Division题目：Given a list of positive integers, the adjacent integers will perform the float division. For example, [2,3,4] -> 2 / 3 / 4.However, you can add any number of par...

leetcode 91.Decode Ways题目：A message containing letters from A-Z is being encoded to numbers using the following mapping:'A' -> 1'B' -> 2...'Z' -> 26Given a non-empty string containing...

leetcode 334. Increasing Triplet Subsequence题目：Given an unsorted array return whether an increasing subsequence of length 3 exists or not in the array.Formally the function should:Return true if ...