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spark2.2.0

Spark SQL, DataFrames and Datasets Guide

Spark SQL, DataFrames and Datasets Guide 概要 Spark SQL是用于结构化数据处理的Spark模块，与基本的Spark RDD API不同， Spark SQL API可以为结构化数据提供更多的信息。在底层，Spark SQL使用这些额外的信息进行进一步优化执行过程。有几种与Spark SQL进行交互的方法，主要包括SQL和Dataset...

Posted by Johnnwen on August 1, 2017

排序算法

排序算法 1. 快速排序 #include <iostream> #include <vector> using namespace std; void quickSort(vector<int> &nums,int start,int end){ int i = start,j = end,temp = nums[start],t...

Posted by Johnnwen on July 15, 2016

Binary Tree Level Traversal

Binary Tree Level Traversal(二叉树遍历问题) 102. Binary Tree Level Order Traversal 题意 Given a binary tree, return the level order traversal of its nodes’ values. (ie, from left to right, level by level)...

Posted by Johnnwen on July 8, 2016

Merge questions

Merge questions leetcode 88. Merge Sorted Array 题意 Given two sorted integer arrays nums1 and nums2, merge nums2 into nums1 as one sorted array. Note: You may assume that nums1 has enough space ...

Posted by Johnnwen on June 20, 2016

Tomcat安装和配置

omcat安装和配置部署并启动tomcat服务器。（1）解压apache-tomcat-x.x.x.zip到一个非中文目录下（2）配置环境变量：java_home（jre_home）指向JDK的安装根目录（3）通过双击apache-tomcat-x.x.x\bin目录下的start.bat启动服务器（4）可以在浏览器...

Posted by Johnnwen on June 1, 2016

JavaWeb中文乱码问题

JavaWeb中文乱码问题在JSP页面中输入中文乱码请求参页面后不出现乱码：保证<%@ page language=”java” contentType=”text/html; charset=UTF-8” pageEncoding=”UTF-8”%> charset和pageEncoding编码一致，且都支持中文，通常建议取值UTF－8，还需要保...

Posted by Johnnwen on June 1, 2016

leetcode 46. Permutations

leetcode 46. Permutations 题意 Given a collection of distinct numbers, return all possible permutations. For example [1,2,3] have the following permutations: [1,2,3], [1,3,2], [2,1,3], [2,3,1], ...

Posted by Johnnwen on May 31, 2016

leetcode 349. Intersection of Two Arrays

leetcode 349. Intersection of Two Arrays 题意 Given two arrays, write a function to compute their intersection. Example: Given nums1 = [1, 2, 2, 1], nums2 = [2, 2], return [2]. Note: Each ele...

Posted by Johnnwen on May 25, 2016

基于SSH框架的后台开发流程

代码框架图基本开发流程 1.加入Spring 1）加入jar包 2）配置web.xml文件 3)加入Spring配置文件 2.加入Hibernate 1）同时建立持久化类，和其对应的.hbm.xml文件，生成对应的数据表 2） Spring整合Hibernate a)加入jar包 b)在类路径下加入Hibernate.cfg.xml文件，在其中配置Hibernate...

Posted by Johnnwen on May 18, 2016

leetcode 116. Populating Next Right Pointers in Each Node

leetcode 116. Populating Next Right Pointers in Each Node 题意 Given a binary tree struct TreeLinkNode { TreeLinkNode *left; TreeLinkNode *right; TreeLinkNode *next; } Pop...

Posted by Johnnwen on May 16, 2016