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Article summary | Boss, have a nice weekend

Hello everyone, I am Lao Wu. Weekends are my time to bring my baby, so I won t post technical articles. Take advantage of your free time, summarize the articles for the bosses. Stop talking nonsense, roll up your sleeves and do it. Linux system programming Linux-C programming | 3 minutes to quickly understand signal-driven IO Linux-C programming/ process communication/ realize file server based on SysV message queue Linux-C programming / multithreading / a simple and reliable thread pool impleme

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Java starts from 0!

Let us learn Java together! Front Environment configuration If you want to do well, you must first sharpen your tools and configure the environment honestly. Environment configuration please refer to: www.runoob.com/java/java-e... Then there is a ritual thing-helloworld! Create a new project, name it helloworld, add a java class, the code is as follows: public class helloworld { public static void main(String[] args) { System.out.println("Hello World"); } } Copy code The results are as follows:

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Linux network programming uses epoll to implement a high-performance TCP Echo server

my.oschina.net/u/989096/bl... # . Foreword In Linux network programming, it is a common method to use I/O multiplexing to handle large-scale concurrent connections.select,poll,epoll, This article mainly describesepollHow to use and useepollA high-performance Echo server is implemented, that is, the received data is returned to the client as it is. Final analysis andselectwithpollAnd introduce some common problems. # epoll Introduction##1. Related functions and data structures # include <sys/e

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Getting started with CMake, starting with examples, explaining common usage of CMake, such as the usage of aux_source_directory

www.hahack.com/codes/cmake... sourceforge.net/projects/qm...  --qmake convert cmake gadget\ \ What is CMake All problems in computer science can be solved by another level of indirection. David Wheeler You may have heard of several Make tools, such as  GNU Make  , QT's  qmake  , Microsoft's  MS nmake , BSD Make ( pmake ), Makepp , and so on. These Make tools follow different specifications and standards, and the format of the Makefile executed is also very different

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One data definition

1 database schema definition Contains operations such as database creation, selection, modification, deletion, and viewing 1.1 Create a database CREATE DATABASE database name; / / Examples of the CREATE DATABASE db_name; duplicated code 1.2 Choose a database  use database name; / / Example use db_name; Copy code 1.3 Modify the database  SHOW the CREATE DATABASE test_db; / / See the definition statement test_db database execution results are shown below: + ----------+-------------------

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How to create user interaction with events in Vue

The author chooses " open mental illness " as" Write for the Nation " project to receive donations. Introduction In the development of Vue.js , the client's web browser reads HTML and JavaScript, and renders the web page according to the instructions written by the developer. But web pages or applications need to process not only data, but also user interaction. In order to do this, developers use events in JavaScript when users interact with HTML execute code interacts elements. An event can ca

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[Path planning] Matlab source code for solving multi-traveling salesman MTSP problem based on ant colony

1. Introduction to Ant Colony Algorithm     The ant colony algorithm is a kind of bionic algorithm derived from the simulation of the path-finding method of the natural ants: during the movement of the ant, it can leave pheromone substances on the path it passes for information transmission. And the ants can perceive this substance during the movement process, and use it to guide their movement direction. The behavior of an ant colony composed of a large number of ants exhibits a posit

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github dalao yuanguangxin github star github.com/yuanguangxi ZooKeeper CAP P C A ZooKeeper CP ZooKeeper ZooKeeper leader ZooKeeper BASE BASE BASE CAP CA CAP 0.5 1~2 ZooKeeper ZooKeeper ZooKeeper ZAB ZAB Zookeeper Leader Leader Leader Follower Leader Leader Leader FastLeaderElection( ) 5 1,2,3,4,5, 1 1 Looking 2 1 2 2 LOOKING 3 1,2 3 3 3 leader 1,2 follower 4 1,2,3 4 3 4 follower 5 4 follower zk zk linux zk zk 1M client znode watcher znode client zk client znode zk zk mylock A mylock mylock B A

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Shortest path

ACM template Dijkstra single source shortest path adjacency matrix form /* * Single source shortest path, Dijkstra algorithm, adjacency matrix form, complexity O(n^2) * Find the shortest path from the source beg to all points, the number of vertices of the incoming graph and the adjacency matrix cost[][] * Return the shortest path lowcost[] of each point, path pre[], pre[i] record the parent node on the path from beg to i, pre[beg] = -1 * The type of path weight can be changed, but the weight mu

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On the second side of Ali, the interviewer actually asked the TCP three-way handshake so carefully

TCP's three-way handshake and four-time wave of hands can be said to be classic questions that are often talked about. They are also commonly used as interview questions in major companies, and have a certain level of discrimination. It seems to be a simple interview question. If your answer does not meet the expectations of the interviewer, it may be cold. This article will focus on a series of core questions related to the three-way handshake and four-time wave of hands, and share how to answe

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Hyperopt Chinese document: FMin

FMin Font Tian translated this article on 22 December 2017 This page is about hyperopt.fmin() The basic tutorial. Mainly wrote how to write a function that can be optimized with fmin, and how to describe the search space of fmin. Hyperopt's job is to find the scalar value through a set of possible parameters, the best value of the possibly-stochastic function (note that stochastic and random are not exactly the same in mathematics). Although many optimization packages assume that these inputs ar

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After reading the summary of JVM knowledge points of Ali P7 technology big cow, I actually got 3 offers from big manufacturers

Hello, today I will share the JVM with you children's shoes, please take out a small book and write it down! Memory overflow Out of Memory (OOM) refers to the existence of unrecyclable memory or excessive memory usage in the application system, which ultimately makes the memory used by the program running larger than the maximum memory that can be provided. The explanation of the memory overflow in the official document is that there is no free memory, and the garbage collector cannot provide mo

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How to take care of your microservices-build a log aggregation system

Preface Recently, some students in the team have invested a lot of energy in building an ELK-based log aggregation system. Personally, I think they just made suggestions for ideas, verification and sorting, and I wrote a blog by the way. Introduction to ELK es+logstask+kibana+filebeat. Basic structure ELK is shown in the following figure. Compared with the traditional ELK architecture, filebeat is also added in this picture, because with the development and popularization of microservices in rec

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[Path planning] Matlab source code for solving multi-traveling salesman MTSP problem based on ant colony

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423.LeetCode

Sum of two numbers Method 1: Violent enumeration Time complexity: O(N^2), where N is the number of elements in the array. In the worst case, any two numbers in the array must be matched once. Space complexity: O(1). var Solution = function(nums,target){ const sorted = new Array(2).fill(0); for(let i = 0;i<nums.length;++i){ for(let j = i+1;j<nums.length;++j){ if(nums[j]+nums[i]==target){ sorted[0] = i; sorted[1] = j; return sorted; } } } return sorted; }; Copy code Method two: hash table Ti

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The rankings of the summary stage in 2021 are here to be announced~

In 2021, the mid-year summary will be published. Logitech mechanical keyboard and other exquisite prizes are waiting for you to win The mid-2021 summary activity is coming to an end~ Everyone's calling for rankings, Nuggets helped to sort it out~ Finishing deadline: July 12, 24:00 Come take a look at your ranking~ RankNuggets personal homepageArticle detailsintegral1Cat MeowThe mental journey of a 23-year-old deep-floating female | Mid-2021 summary5541.92Luo ZhuLove her, give her a home in Hangz

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Gateway processing flow of Zuul source code analysis

Zuul processing flow 1. spring-cloud-starter-zuul starter Let's first check what is in the spring-cloud-starter-zuul starter package. The focus here is the pom.xml file, ZuulDeprecationWarningAutoConfiguration.java Open org.springframework.cloud/spring-cloud-starter-zuul/pom.xml, you can see that it depends on spring-cloud-starter-netflix-zuul <?xml version= "1.0" encoding= "UTF-8" ?> <project xmlns= "http://maven.apache.org/POM/4.0.0" xmlns:xsi= "http://www.w3.org/2001/XMLSchema-instan

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Liuctic Computational Geometry Library

ACM template Liuctic Computational Geometry Library /* * Liuctic's computational geometry library * p-Lpoint ln, l-Lline ls-Llineseglr-Lrad * The distance between two points on the plane p2pdis * (P1-P0)*(P2-P0) cross product xmulti * Determine whether two line segments intersect lsinterls * Determine whether the point p is ponls on the line segment l * Determine whether two points are equal Euqal_Point * Line segments intersect at non-end points lsinterls_A * Determine whether the point q is pi

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MATLAB and C++ Realization of Matrix LU Decomposition

One: Matrix LU decomposition The purpose of matrix LU decomposition is to convert a non-singular matrixAAA breaks down intoA=LUA=LUA=The form of L U , whereLLL is a main diagonal11The lower triangular matrix of 1 ;UUU is an upper triangular matrix. such asA=[124372233]A= \begin{bmatrix} 1 & 2 & 4 \\ 3 & 7 & 2 \\ 2 & 3 & 3 \\ \end{bmatrix}A= 132273423 , We finally have to decompose into the following form: [1003102 11] [12401 1000 15]\begin{bmatrix} 1 & 0 & 0 \\ 3

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High German vector diagram-polygon and circle drawing and editing

Preface A high-tech map was used in the project to make an electronic fence, which was then recorded. Instance <!doctype html > < html > < head > < meta charset = "utf-8" > < meta http-equiv = "X-UA-Compatible" content = "IE=edge" > < meta name = "viewport" content = "initial-scale=1.0, user-scalable=no, width=device-width" > < style > html , body , #container { width : 100% ; height : 100% ; } </ style > < title > Drawing and editing of poly

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