xiaoyongyong

摘要： 对于一个数组 arr[1...n]，Fenwick Tree 可以支持两种操作： update(i, delta)：将 arr[i] += delta query(i)：返回前缀和 arr[1] + arr[2] + ... + arr[i] 它的时间复杂度为： 构建：O(n) 查询：O(log n 阅读全文

摘要： 3447. Assign Elements to Groups with Constraints Solved Medium Topics Companies Hint You are given an integer array groups, where groups[i] represents 阅读全文

摘要： 1878. Get Biggest Three Rhombus Sums in a Grid You are given an m x n integer matrix grid​​​. A rhombus sum is the sum of the elements that form the b 阅读全文

摘要： 126. Word Ladder II A transformation sequence from word beginWord to word endWord using a dictionary wordList is a sequence of words beginWord -> s1 - 阅读全文

摘要： 使用着色法来判定一个图是否为二分图，或者是否包含奇环（包含奇环的话就不是二分图） 785. Is Graph Bipartite? There is an undirected graph with n nodes, where each node is numbered between 0 and 阅读全文

摘要： 564. Find the Closest Palindrome Given a string n representing an integer, return the closest integer (not including itself), which is a palindrome. I 阅读全文

摘要： 296. Best Meeting Point Given an m x n binary grid grid where each 1 marks the home of one friend, return the minimal total travel distance. The total 阅读全文

摘要： 1526. Minimum Number of Increments on Subarrays to Form a Target Array You are given an integer array target. You have an integer array initial of the 阅读全文

摘要： 3186. Maximum Total Damage With Spell Casting A magician has various spells. You are given an array power, where each element represents the damage of 阅读全文

摘要： 给定一个数组，没有重复元素，要将其排列为一小一大一小一大, 比如： [8,6,7,3,4,5] 结果是: [6,8,3,7,4,5] [1,2,3,4,5] 结果是： [1,3,2,5,4] one pass void sort(int[] arr) { for(int i = 0; i < arr 阅读全文