[HAOI2015] tree dyeing

First of all, a simple idea is to make \ (dp_{i, j} \) as the maximum benefit of selecting \ (j \) black spots in the subtree with \ (I \) as the root, but you will find that no matter how to transfer this thing, it needs to involve depth and sum. If we record depth and sum, we can't pass this problem. We might as well split each side of each p ...

Posted by 947740 on Wed, 25 May 2022 19:14:42 +0300

JDBC operation data and DAO design pattern in actual combat

Using JDBC to manipulate data 1. Using JDBC to write large text data to the database Purpose: to java and other text files are written to the corresponding fields of the corresponding table by connecting the database with JDBC. 1. Table structure 2. Documents 3. Implementation code for inserting text package LoadFileTest; import driver.JDB ...

Posted by schoi on Wed, 25 May 2022 18:54:45 +0300

Didn't you say you would Aop?

Early in the morning, Xiao Wang hurried to me and said: brother Zhou, I want to ask about the function of logging. Because a project of the company needs to be connected with other platforms, we need to provide them with a set of interfaces. Yesterday, I assigned Xiao Wang to record the interface log. The following is my main conversation with ...

Posted by Emperio on Wed, 25 May 2022 18:24:15 +0300

Double stack sorting (bipartite graph coloring)

subject A very mellow topic Problem solution The key to this problem is to analyze whether two numbers can be on the same stack According to this logic, the general idea of this topic is: If a number xxx, 111~(x − 1)(x-1)(x − 1) has been popped up, then xxx will pop up, otherwise xxx will remain in the stack, and all subsequent numb ...

Posted by danrah on Wed, 25 May 2022 18:14:21 +0300

Dahua design mode reading notes (builder mode)

People: small dish, big bird Event: the small dish and the big bird went to have a snack. The small dish ate a bowl of delicious fried noodles, and then the big bird wanted to eat and ordered a bowl, but found that this bowl did not put salt. Why did the same cook cook cook fried noodles twice, the first bowl was delicious, but the second bowl ...

Posted by scm24 on Wed, 25 May 2022 18:14:28 +0300

Build your own MVC framework based on Koa2

Express and Koa are lightweight web frameworks. Although they are flexible and simple, and you can start the server in a few lines of code, with the complexity of the business, you will soon find that you need to manually configure various middleware. Moreover, because this kind of web framework does not restrict the directory structure of the ...

Posted by andymt on Wed, 25 May 2022 18:10:42 +0300

Remember a secondary development based on vant components

Introduction When developing the H5 project on the mobile phone, I chose the vue + vant ecosystem, and when using PullRefresh pull down refresh component, you need to customize the display. However, there are 3 pages under the home page Tab that need to be customized, and they are encapsulated as a component for convenience. source code The fol ...

Posted by acabrera on Wed, 25 May 2022 18:08:47 +0300

HI group purchase system development (system development)

HashMap is stored using Hash table. In order to solve the conflict of Hash table, open address method and chain address method can be used to solve the problem. HashMap in Java adopts chain address method. Chain address method, in short, is the combination of array and linked list. There is a linked list structure on each array element. When th ...

Posted by Jonob on Wed, 25 May 2022 18:02:25 +0300

MySql advanced master-slave synchronization ☆

Master slave synchronization of MySql advanced 1. Replication overview This means that the master and slave databases can be synchronized again by transferring these data to the master and slave databases through the DDL. MySQL supports the replication of one master database to multiple slave databases at the same time. The slave database ca ...

Posted by upit on Wed, 25 May 2022 17:55:35 +0300

20211202 "Python Programming" Experiment 4 Python Comprehensive Practice Experiment Report

20211202 "Python Programming" Experiment 4 Python Comprehensive Practice Experiment Report   Course: "Python Programming"Class: 2112Name: Wang JinshuoStudent ID: 20211202Experimental teacher: Wang ZhiqiangExperiment Date: May 24, 2022Compulsory/Elective: Public Elective   1. Experimental content   1. Inspiration:        One ...

Posted by Mhz2020 on Wed, 25 May 2022 17:54:30 +0300