leetcode

Leetcode (4) | | Longest palindromic Substring and manacher linear algorithmPrefaceThis article is the fifth question of Leetcode, did not think that the speed of doing these questions will be so slow, all of the work in this above, the only blame their basic poor. This article mainly describes the longest palindrome substring used to solve a string using the Manacher linear algorithm.Topics Given

Index: [Leetcode] leetcode key index (C++/JAVA/PYTHON/SQL)Github:https://github.com/illuz/leetcode027. Remove Element (Easy) link :Title: https://oj.leetcode.com/problems/remove-element/Code (GitHub): Https://github.com/illuz/leetcodeTest Instructions :Deletes all numbers in an array with a value of elem.Analysis :Use two pointers, one for the position to be placed, and one for the scan pointer.Because it's

Index: [Leetcode] leetcode key index (C++/JAVA/PYTHON/SQL)Github:https://github.com/illuz/leetcode022.generate_parentheses (Medium)links：Title: https://oj.leetcode.com/problems/generate-parentheses/Code (GitHub): Https://github.com/illuz/leetcodeTest Instructions：Produces all valid strings with n-brackets.Analysis： Using DFS can be done quickly, can add ' (' Add ' (', can add ') ' Add ') '. (The fo

Index: [Leetcode] leetcode key index (C++/JAVA/PYTHON/SQL)Github:https://github.com/illuz/leetcode023. Merge k Sorted Lists (Hard)links：Title: https://oj.leetcode.com/problems/merge-k-sorted-lists/Code (GitHub): Https://github.com/illuz/leetcodeTest Instructions：and 021. Merge two Sorted Lists (easy) is similar, this time to merge K.Analysis：It is obvious that you can think of using the function of the comp

Index: [Leetcode] leetcode key index (C++/JAVA/PYTHON/SQL)Github:https://github.com/illuz/leetcode006.zigzag_conversion (Easy)links：Title: https://oj.leetcode.com/problems/zigzag-conversion/Code (GitHub): Https://github.com/illuz/leetcodeTest Instructions：Arranges a string in a line that is written in horizontal order.Analysis：Direct simulation on the line.Code: C + +:Class Solution {Public:string convert (

Index: [Leetcode] leetcode key index (C++/JAVA/PYTHON/SQL)Github:https://github.com/illuz/leetcode002.add_two_numbers (Medium)links：Title: https://oj.leetcode.com/problems/add-two-numbers/Code (GitHub): Https://github.com/illuz/leetcodeTest Instructions：A new list that is generated by adding two lists.Analysis：Direct simulation is possible.Code：C++:Class Solution {public: listnode *addtwonumbers (ListNod

Index: [Leetcode] leetcode key index (C++/JAVA/PYTHON/SQL)Github:https://github.com/illuz/leetcode036. Valid Sudoku (Easy)links：Title: https://leetcode.com/problems/valid-sudoku/Code (GitHub): Https://github.com/illuz/leetcodeTest Instructions：Determine if a Sudoku is valid.Effective Sudoku is not forced to have a solution.Analysis：As long as there is no same number in the same row, column, block.Open the n

Index: [Leetcode] leetcode key index (C++/JAVA/PYTHON/SQL)Github:https://github.com/illuz/leetcode035. Search for a Range (Medium)links：Title: https://leetcode.com/problems/search-for-a-range/Code (GitHub): Https://github.com/illuz/leetcodeTest Instructions：Finds a range of numbers in an ordered array. (because the number is duplicated)Analysis：Or two-point search variants. (c + +) directly with C

Index: [Leetcode] leetcode key index (C++/JAVA/PYTHON/SQL)Github:https://github.com/illuz/leetcode033. Search in rotated Sorted Array (hard)links：Title: https://leetcode.com/problems/search-in-rotated-sorted-array/Code (GitHub): Https://github.com/illuz/leetcodeTest Instructions：Find a number in an ordered array that has been rotated.For example 4 5 6 7 0 1 2 , a "rotated ordered array".Analysis：This is the

One leetcode a day . This series of articles has been uploaded to my Github, address: Zeecoder ' s GithubWelcome to my Sina Weibo Weibo, my Sina WeiboWelcome reprint, Reprint please indicate the source (i) topic Given an integer (Signed/bits), write a function to check whether it are a power of 4. Example:Given num =, return true. Given num = 5, return false. Follow up:could You solve it without loops/recursion? (ii) problem solving The main idea: to

points to any node in the list or null. The first step is to create the corresponding n ', the n ' link after n, according to each node n of the original linked list, and the second step is to set the m_psibling of the nodes on the linked list; The third step is to split the long list into two: Linking the odd-numbered nodes is the original linked list, Linking the nodes of even locations is the list of duplicates. Merge of 82 non-intersecting ordered linked listsIdea: The main study of the mer

Candy There is N children standing in a line. Each child is assigned a rating value. You is giving candies to these children subjected to the following Requirements:each child must has at least one candy. Children with a higher rating get more candies than their neighbors. What's the minimum candies you must give? The key to this problem: or examining. Feel Leetcode topic examining are difficult not to judge clearly the topic to do, often very waste

repeated until the last bar with the height of 0 is traversed, triggering the last pop-up and the last area calculation, after which the stack is empty.(4) Returns the maximum area value.The code below, which is not the height of the stack, but the index of height, the advantage of doing so does not affect the width of the calculation. Code from water fish-[leetcode] largest Rectangle in histogram problem solving report1:intLargestrectanglearea ( vec

Design and implement a data structure for Least recently Used (LRU) cache. It should support the following operations: get and set .get(key)-Get The value ('ll always be positive) of the key if the key exists in the cache, otherwise return-1.set(key, value)-Set or insert the value if the key is not already present. When the cache is reached its capacity, it should invalidate the least recently used item before inserting a new item.Basic ideas:Work with a map to find the problem.Use list maintena

) {//Assuming M is less than n if(M > N)returnFind_kth (B, N, A, M, K);if(M = =0)returnb[k-1];if(k = =1)//Termination conditions return min(a[0], b[0]);intI_a =min(M, k/2);intI_b = k-i_a;if(a[i_a-1] 1])returnFind_kth (A+i_a, M-i_a, B, N, k-i_a);Else if(a[i_a-1] > b[i_b-1])returnFind_kth (A, M, B+i_b, N-i_b, K-i_b);Else returna[i_a-1]; }Reference: Https://github.com/soulmachine/leetcode

Title: https://leetcode.com/problems/3sum-closest/"Label" Array; Pointers"Personal Analysis"This question and its sister problem 3Sum very similar, will not say more, specific analysis can refer to [leetcode][015] 3Sum1 Public classSolution {2 Public intThreesumclosest (int[] Nums,inttarget) {3 intresult =Target;4 intLen =nums.length;5 if(Len ) {6 return0;7 }8 Arrays.sort (nums);9 for(inti = 0

GivenNnon-negative integersa1 ,a2 , ...,an , where each represents a point at coordinate (I,ai ).NVertical lines is drawn such that the both endpoints of lineIis at (I,ai ) and (I, 0). Find lines, which together with X-axis forms a container, such that the container contains the most water.Note:you may not slant the container.This problem is very violent, equivalent to find two "planks", of which the short height of that * two between the distance. So our first thought was the Brute force O (n^2

Description:Count the number of prime numbers less than a non-negative number, nClick to show more hints.Credits:Special thanks to @mithmatt for adding this problem and creating all test cases.For all primes within N, previously seen a topic, by marking out all non-primes, and then finding the prime number, the code is as follows:1 Public intCountPrimes (intN) {2 if(n = = 0 | | n = = 1 | | n = = 2)3 return0;4 int[] flag =New int[n];5 for(inti = 2; I ) {6

. So the distance from 2 to 4 is 2n-2-2i, if the position of 2 is J, then the position of 4 is j+2n-2-2i,8 position is j+2n-2.The code is as follows:stringConvertstringSintnRows) { if(s.length () = =0|| nrows0) return ""; if(NRows = =1) returns; stringRes; intSize =2*nrows-2; for(inti =0; i ) for(intj = i; J size) {Res+=S[j]; if(i!=0 I! = nrows-1){ inttemp = j+size-2*i; if(Temp s.size ()) Res+=S[temp]; } } returnRes; }REF:[1]. Http://www.cnblogs

Leetcode Address: https://leetcode.com/problems/maximum-gap/description/Title DescriptionGiven an unordered array, find the maximum interval between the sorted elements.It is required to be implemented with linear time complexity.For example: The input is "3,6,9,1,10" and the output should be the maximum interval of 3.Problem analysisLinear time complexity implementation, it means that the element cannot be sorted first, because the complexity of this