Given an array of integers A with even length, return true if and only if it is possible to reorder it such that A[2 * i + 1] = 2 * A[2 * i] for every 0 <= i < len(A) / 2.   Example 1: Input: [3,1,3,6] Output: false Example 2: Input: [2,1,2,6] Outpu…

Given an array of integers A with even length, return true if and only if it is possible to reorder it such that A[2 * i + 1] = 2 * A[2 * i] for every 0 <= i < len(A) / 2. Example 1: Input: [3,1,3,6] Output: false Example 2: Input: [2,1,2,6] Output:…

Given an array of integers A with even length, return true if and only if it is possible to reorder it such that A[2 * i + 1] = 2 * A[2 * i] for every 0 <= i < len(A) / 2.   Example 1: Input: [3,1,3,6] Output: false Example 2: Input: [2,1,2,6] Outpu…

Given an array of integers A with even length, return true if and only if it is possible to reorder it such that A[2 * i + 1] = 2 * A[2 * i]for every 0 <= i < len(A) / 2.   Example 1: Input: [3,1,3,6] Output: false Example 2: Input: [2,1,2,6] Output…

Given an array of integers A with even length, return true if and only if it is possible to reorder it such that A[2 * i + 1] = 2 * A[2 * i] for every 0 <= i < len(A) / 2. Example 1: Input: [3,1,3,6] Output: false Example 2: Input: [2,1,2,6] Output:…

题目如下: Given an array of integers A with even length, return true if and only if it is possible to reorder it such that A[2 * i + 1] = 2 * A[2 * i] for every 0 <= i < len(A) / 2. Example 1: Input: [3,1,3,6] Output: false Example 2: Input: [2,1,2,6] O…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 日期 题目地址:https://leetcode.com/problems/array-of-doubled-pairs/description/ 题目描述 Given an array of integers A with even length, return true if and only if it is possible to reord…

数组基础 数组是最基础的数据结构,特点是O(1)时间读取任意下标元素,经常应用于排序(Sort).双指针(Two Pointers).二分查找(Binary Search).动态规划(DP)等算法.顺序访问数组.按下标取值是对数组的常见操作. 相关LeetCode题: 905. Sort Array By Parity  题解 922. Sort Array By Parity II  题解 977. Squares of a Sorted Array  题解 1150. Check If a…

请点击页面左上角 -> Fork me on Github 或直接访问本项目Github地址:LeetCode Solution by Swift    说明:题目中含有$符号则为付费题目. 如:[Swift]LeetCode156.二叉树的上下颠倒 $ Binary Tree Upside Down 请下拉滚动条查看最新 Weekly Contest!!! Swift LeetCode 目录 | Catalog 序        号 题名Title 难度     Difficulty  两数之…

955. Delete Columns to Make Sorted II We are given an array A of N lowercase letter strings, all of the same length. Now, we may choose any set of deletion indices, and for each string, we delete all the characters in those indices. For example, if w…

Contest 111 (题号941-944)(2019年1月19日,补充题解,主要是943题) 链接:https://leetcode.com/contest/weekly-contest-111 [941]Valid Mountain Array(第一题 3分)(google tag) 判断一个数组是不是 Mountain 数组. Mountain 数组的定义是 A.length >= 3There exists some i with 0 < i < A.length - 1 su…

Array *532. K-diff Pairs in an Array 方案一:暴力搜索, N平方的时间复杂度,空间复杂度N 数组长度为10000,使用O(N平方)的解法担心TLE,不建议使用,尽管最终验证还是可以过. 方案二:哈希 时间复杂度N 空间复杂度N *1.two sum 思路: 使用hash, 顺序遍历数组,并记录每一个出现过的元素值和其下标,当遍历到当前元素时,查找target-当前元素值 是否出现在map中,存在则返回结果 *16. 3Sum Closest 思路一:暴力 fo…

映射是键值对偶的集合.Scala有一个通用的叫法——元组:n个对象的聚集,并不一定要相同的类型. 构造映射 键A -> 值B scala> val scores = Map()//不可变映射 scores: scala.collection.immutable.Map[String,Int] = Map(wcc100 -> ) scala> val scores1 = scala.collection.mutable.Map()//可变的映射 scores1: scala.coll…

Container,用于动态地创建.注入依赖单元,映射依赖关系等功能,减少了许多代码量,降低代码耦合程度,提高项目的可维护性. namespace yii\di; use ReflectionClass; use Yii; use yii\base\Component; use yii\base\InvalidConfigException; use yii\helpers\ArrayHelper; /** * Container implements a [dependency injecti…

ServiceLocator,服务定位类,用于yii2中的依赖注入,通过以ID为索引的方式缓存服务或则组件的实例来定位服务或者组件: namespace yii\di; use Yii; use Closure; use yii\base\Component; use yii\base\InvalidConfigException; /** * ServiceLocator implements a [service locator](http://en.wikipedia.org/wiki/S…

web/Application类的注释,继承base/Application类,针对web应用的一些处理: namespace yii\web; use Yii; use yii\base\InvalidRouteException; /** * Application is the base class for all web application classes. * Application 是所有web应用的基类 * * @property string $homeUrl The hom…

Widget类是所有小部件的基类,开始,结束和渲染小部件内容的方法的注释: namespace yii\base; use Yii; use ReflectionClass; /** * Widget is the base class for widgets. * Widget是所有小部件的基类 * * @property string $id ID of the widget. * @property \yii\web\View $view The view object that can…

463. Island Perimeterhttps://leetcode.com/problems/island-perimeter/就是逐一遍历所有的cell,用分离的cell总的的边数减去重叠的边的数目即可.在查找重叠的边的数目的时候有一点小技巧,就是沿着其中两个方向就好,这种题目都有类似的规律,就是可以沿着上三角或者下三角形的方向来做.一刷一次ac,但是还没开始注意codestyle的问题,需要再刷一遍. class Solution { public: int islandPerime…

官网原文:http://www.yiiframework.com/doc/guide/1.1/zh_cn/database.arr 官网中后半段为英文,而且中文的内容比英文少一些,先放到这里,之后有时间再翻译. 我们已经了解了怎样使用 Active Record (AR) 从单个数据表中获取数据. 在本节中,我们讲解怎样使用 AR 连接多个相关数据表并取回关联(join)后的数据集. 为了使用关系型 AR,我们建议在需要关联的表中定义主键-外键约束.这些约束可以帮助保证相关数据的一致性和完整性.…

Module类,属性的注释和构造函数的注释: <?php /** * @link http://www.yiiframework.com/ * @copyright Copyright (c) 2008 Yii Software LLC * @license http://www.yiiframework.com/license/ */ namespace yii\base; use Yii; use yii\di\ServiceLocator; /** * Module is the base…

Yii2请求处理流程: 首先:项目路径/web/index.php (new yii\web\Application($config))->run();//根据配置文件创建App实例,先实例化yii\web\Application(),然后调用run()方法 该语句可分为两步: $application = new yii\web\Application($config);//实例化app $application->run();//调用run()方法 $config 为配置文件,通过 req…

Action类,控制器中方法的基类: namespace yii\base; use Yii; /** * Action is the base class for all controller action classes. * Action是所有控制器方法的基类 * Action provides a way to reuse action method code. An action method in an Action * class can be used in multiple c…

Object 是一个基础类,实现了属性的功能,其基本内容如下: namespace yii\base; use Yii; /** * Object is the base class that implements the *property* feature. * Object是一个基础类,实现了属性的功能 * A property is defined by a getter method (e.g. `getLabel`), and/or a setter method (e.g. `se…

控制台程序. public class Point { // Create a point from its coordinates public Point(double xVal, double yVal) { x = xVal; y = yVal; } // Create a point from another point public Point(Point point) { x = point.x; y = point.y; } // Convert a point to a str…

控制台程序 定义Point类: public class Point { // Create a point from its coordinates public Point(double xVal, double yVal) { x = xVal; y = yVal; } // Create a point from another point public Point(Point point) { x = point.x; y = point.y; } // Convert a point…

step 1: 函数功能说明 mixChannels主要就是把输入的矩阵(或矩阵数组)的某些通道拆分复制给对应的输出矩阵(或矩阵数组)的某些通道中,其中的对应关系就由fromTo参数制定. step 2: 函数原型讲解 C++:   void  mixChannels (const Mat*  src , int  nsrc , Mat*  dst , int  ndst , const int*  fromTo , size_t  npairs ); src– Input array or v…

Introduction All of the configuration files for the Laravel framework are stored in the app/config directory. Each option in every file is documented, so feel free to look through the files and get familiar with the options available to you. Sometime…

Widget类是所有部件的基类.yii2\base\Widget.php <?php /** * @link http://www.yiiframework.com/ * @copyright Copyright (c) 2008 Yii Software LLC * @license http://www.yiiframework.com/license/ */ namespace yii\base; use Yii; use ReflectionClass; /** * Widget is…

Module类是模块和应用类的基类. yiisoft\yii2\base\Module.php <?php /** * @link http://www.yiiframework.com/ * @copyright Copyright (c) 2008 Yii Software LLC * @license http://www.yiiframework.com/license/ */ namespace yii\base; use Yii; use yii\di\ServiceLocator;…

Controller控制器类,是所有控制器的基类,用于调用模型和布局. <?php /** * @link http://www.yiiframework.com/ * @copyright Copyright (c) 2008 Yii Software LLC * @license http://www.yiiframework.com/license/ */ namespace yii\base; use Yii; /** * Controller is the base class for…