[Data structure] Implementation of the heap

Heap 1. Heap: a binary tree 1 1 2. The concept and structure of a heap 2 11 3. The realization of a heap 3 21 3.1 Creating a heap structure 31 22 3.2 Heap initialization 32 35 3.3 Heap insertion 33 55 3.4 Heap upward adjustmentMethod (up) 34 up 79 3....

2022-11-24 | Deliberately Plant Flowers Unintentionally Plant Willows | 201 views

Linux - file descriptor (fd) and redirection, dup/dup2

目录 一.文件描述符 %E4%B8%80.%E6%96%87%E4%BB%B6%E6%8F%8F%E8%BF%B0%E7%AC%A6 (一).含义 %EF%BC%88%E4%B8%80%EF%BC%89.%E5%90%AB%E4%B9%89 (二).使用 %C2%A0%EF%BC%88%E4%BA%8C%EF%BC%89.%E4%BD%BF%E7%94%A8 (三).标准输入/输出/错误 %EF%BC%88%E4%B8%89%EF%BC%89.%E6%A0%87%E5%87%86%E8%BE%9...

2022-11-24 | stay at home | 727 views

Design pattern - singleton pattern

Eight singleton design pattern, as well as their advantages and disadvantages of the singleton pattern 1 is recommended to use / / / / the hungry type/class after loaded into memory, instantiate an object, the JVM ensure thread safety/simple, practic...

2022-11-24 | Running water 774 | 506 views

Various problems encountered by Spring

Personal profile https://img blog.csdnimg.cn/65df4aaae61a4a4a857adea6f5deec35.png Author profile: Hello everyone, I am yukki.https://img blog.csdnimg.cn/d506882d4ce1427badf186060fefc79b.png Personal homepage: yukki.* One-click three-link mutual encou...

2022-11-24 | 较…… | 671 views

SpringCloud solves Consider defining a bean of type '*Mapper' in your configuration.

The first one is to post @Mapper on the Mapper interface @Repository @Mapper public interface CommodityMapper { // / / Query all commodity information/ @return List Commodity all commodity information/ / List Commodity selectAll ; } The second one is...

2022-11-24 | Zhang Tongyao | 619 views

Talk about Mybatis type conversion registration class TypeHandlerRegistry

Let’s talk about Mybatis’ type conversion registration class TypeHandlerRegistry. In the last article, we mentioned that TypeHandler is an interface for type conversion. It has many implementation classes for different types. TypeHandlerRegistry is u...

2022-11-24 | InfoQ | 919 views

SpringCloud @FeignClient injection cannot find exception

Preface Inter-service calls in Springcloud are called through Feign. In the caller service, we need to define some interface classes annotated with @FeignClient.And add the @EnableFeignClients annotation to the startup class.When the program starts, ...

2022-11-24 | Zhang Tongyao | 214 views

Summary of SpringBoot Mysql failure to store emoji

1. Reasons on the MySQL side: utf8 is not utf 8, only supports up to 3-byte characters, utf8mb4 supports up to 4-byte characters, and emoji expressions have four-byte characters, so the character set of utf8mb4 must be used to save emoticons.Environm...

2022-11-24 | Zhang Tongyao | 930 views

Talk about getting connection of Mybatis data source

Let’s talk about the data source of Mybatis to get the connection. After reading the pushConnection method of PooledDataSource, look at its popConnection method: Get the database connection to get the database connection and call the getConnection me...

2022-11-24 | InfoQ | 668 views

Talk about the type conversion interface TypeHandler of Mybatis

Let’s talk about Mybatis’s type conversion interface TypeHandler mybatis can realize the conversion between jdbc type and java type. Specifically, there is a type converter interface: Type handler interface TypeHandler TypeHandler interface is define...

2022-11-24 | InfoQ | 620 views

CDH6.3.2 deals with Zookeeper vulnerabilities caused by unauthorized access

https://img blogs. Csdnimg. Cn / 752 dd02dcff94a96a418b3ea9c473ab1. PNG (1) the basic situation of the zookeeper zookeeper is distributed collaborative management tools, commonly used to manage system configuration information, provide distributed co...

2022-11-24 | Gargamel MMQ!! | 186 views

18. The Spring source 】 【 factory - key function, a method to create objects: instantiateUsingFactoryMethod ()

Today is the home field of instantiateUsingFactoryMethod, which is the key function of the factory method to create objects in the createBeanInstance method. This is a function with 300+ lines. You deserve to know the witty face.gif First, let's find...

2022-11-24 | AQin1012 | 486 views

docker oracle11g import .dmp file

Environment CentnOS7 Docker version 20.10.18, build b40c2f6 registry.cn hangzhou.aliyuncs.com/helowin/oracle 11g 1. Use XFTP tool to upload the .dmp file to CentOS7 https://img blog.csdnimg.cn/d779ac4c2fcb46ec914c52759bf12e7b.png, Assign the .dmp fil...

2022-11-24 | String-int | 984 views

HTML+CSS+JavaScript imitation Jingdong shopping mall website web front-end production of clothing shopping mall html e-commerce shopping website

Common web design assignment topics have personal, food, company, school, travel, business, pet, electric appliances, tea, home, hotel, dance, anime, clothing, sports, cosmetics, logistics, environmental protection, books, wedding dresses, games, fes...

2022-11-24 | Web site construction | 966 views

HTML+CSS+JavaScript imitation Jingdong shopping website production html static webpage design and production dw static webpage finished template material webpage web front-end webpage design and production div static webpage design

HTML example web page code, this example is suitable for students who are beginners in HTML.In this example, there are css style settings and div style patterns. This example is more comprehensive and helpful for students to learn. This article will ...

2022-11-24 | web site construction | 783 views

HTML+CSS+JavaScript Tanabata Valentine's Day Confession Webpage [Sakura Rain 3D Photo Album] Super Beautiful

This is one of the 100 website confessions in the programmer's confession series, designed to allow anyone to use and create their own confession website for loved ones to see.There are a total of 100 confession websites in this wave, which can be mo...

2022-11-24 | web site construction | 542 views

HUAWEI Machine Test Real Questions Java Realization [Vehicles with the Most Colors] [2022.11 Q4 New Questions]

Catalog topic %E9%A2%98%E7%9B%AE Idea %E6%80%9D%E8%B7%AF Test center %E8%80%83%E7%82%B9 Code Code The content of the topic is at a narrow intersection, only one vehicle can pass per second, and there are only 3 colors of fake vehicles, find out the n...

2022-11-24 | MISAYAONE | 752 views

MySQL database user management and database user authorization

A, 1, the new USER CREATE a database USER management USER 'USER name' @ 'source address IDENTIFIED BY PASSWORD' PASSWORD '.'user name' : specifies the user will create the 'source address: specifies the newly created user can log in on which hosts, y...

2022-11-24 | Jackielong | 446 views

春云阿里巴巴(四)

openFeign configuration log 1. The log level of openFeign: NONE: Do not log the default. BASIC: Only record the request method, url, response status code and execution time.HEADERS: On the basis of basic, add request and response headers FULL: Record...

2022-11-24 | Xi Bing | 345 views

Spring Cloud Alibaba (3)

Replace the Ribbon load balancing strategy Custom strategy 1. Based on the previous article Spring Cloud Alibaba (2) Xibing's blog CSDN blog 'Spring Cloud Alibaba (2) Xibing's blog CSDN blog', I want to replace the ribbon's load balancing strategyMet...

2022-11-24 | Xi Bing | 451 views
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