Jzoj P4261 minimum cost spfa + minimum spanning tree

Main idea: This paper presents an undirected weighted graph composed of nn points and mm edges. Some of the points are black and others are white. Now every white dot must be connected with the nearest black dot through the shortest path (if there are many black dots, you can choose any one of them). We want to minimize the c ...

Posted on Sat, 22 Feb 2020 12:50:21 -0500 by illzz

Python crawler ajax crawls the content of Ma Yun's father's Micro blog

ajax crawling Sometimes when we use Requests to grab the page, the result may be different from what we see in the browser. We can see the normal page data in the browser, but we don't get the result using Requests. The reason is that Requests gets the original HTML document, while the page in the browser is the page passing by again The result ...

Posted on Sat, 22 Feb 2020 12:37:06 -0500 by fifin04

MHA of MySQL high availability cluster

1, MHA introduction At present, MHA (Master High Availability) is a relatively mature solution in the aspect of MySQL high availability. It is developed by yoshimaton (now working for Facebook), a Japanese DeNA company. It is an excellent high availability software for failover and master-slave improvement in MySQL high availability environm ...

Posted on Sat, 22 Feb 2020 12:24:43 -0500 by dahwan

C language: address book management

Functions of address book The address book can be used to store 1000 personal information, each person's information includes: name, gender, age, telephone, address. Besides the most basic function of adding, deleting, modifying and checking, it can also display all information, clear all contacts, sort ...

Posted on Sat, 22 Feb 2020 12:20:30 -0500 by afrancis

python logging duplicate log problem

Original link: https://blog.csdn.net/huilan_same/article/details/51858817 When writing logs with the logging module, I encountered the problem of duplicate printing of logs.That is, the first call in the same script, normally shown, the second call, shows two duplicates, and so on, is very headache. Reason found online: handle object was not de ...

Posted on Sat, 22 Feb 2020 12:08:55 -0500 by []InTeR[]

Engineering practice of implementing distributed FIFO queue based on zookeeper cluster

In the previous paper, we implemented a distributed id generator based on zk cluster. In this paper, we continue to carry out scenario practice based on zk cluster. How do distributed FIFO queues use zk? Code directly. 1, Beans needed to create queues package com.coderman.zookeeper.clusterdemo.queue ...

Posted on Sat, 22 Feb 2020 11:45:25 -0500 by scald

Quantsrat lets R language perform strategic backtracking and quantitative trading like Python

Using the Quantsrat package Quantsrat s are used to build strategies, add metrics, generate signals, generate buying and selling rules, and so on.The results are similar to Python quantification platforms like premium mines, ten thousand mines, and baskets.Because CRAN cannot be installed online, there are still some pits in the installation pr ...

Posted on Sat, 22 Feb 2020 11:28:59 -0500 by chaiwei

14, Learning Scrapy of distributed Crawlers

Scrapy framework Learning objectives Understand the skeleton. Learn how to write spider crawlers. Learn how to write Crawlspider. Learn how to write middleware. Learn pipeline to save data. Learn to use Scrapy with selenium. Learn to use IP proxy in scratch.Introduction to the Scrapy frameworkInstall ...

Posted on Sat, 22 Feb 2020 11:06:49 -0500 by Ludichrist

axis2 document method call

Advantages: it is cumbersome and flexible to use ducument. It's used more now. Because it really gets rid of the coupling we don't want Code: public void addValidation(ServiceClient serviceClient, String tns , String token_str) {         //Because of your different requirements, you can refer to the figure at the bottom to correspond to the sp ...

Posted on Sat, 22 Feb 2020 10:53:42 -0500 by srini_r_r

SpringBoot - realize image upload | alicloud OSS

Preparation Prepare a virtual machine. The virtual machine doesn't have to use Alibaba cloud, but during the recent outbreak, Alibaba cloud has activities, and students can use it for six months free. I set an alarm clock at 7:50 this morning and then I got up to rob the free virtual machine Openi ...

Posted on Sat, 22 Feb 2020 10:48:49 -0500 by robpoe