Articles

About me

I am a master's student in Computer Science (Software Technology Track) at the University of Twente, The Netherlands. I received my Bachelor's degree in Software Engineering from Northwestern Polytechnical University, China.

I want to become a server-side developer and HPC researcher. I am passionate about many areas including, but not limited to, general purpose computing on GPUs (GPGPU), mutation testing, cloud native, containerisation, CI/CD, web development, iOS development, and semantic web. I enjoy the process of researching solutions for software projects, breaking down solutions to work package, and finally solving concrete technical problems. Being well-organized always makes me enthusiastic and energetic. I am currently researching on CUDA and mutation testing (for Master's project), large language model (LLM), iOS development (for a naive music player), and server-side development (for a job).

Yujie LiuLess than 1 minute

Segment Tree 线段树

线段树解决的是「区间和」的问题，且该「区间」会被修改

一个区间的例子是对于 nums = [1, 2, 3, 4, 5] 多次求某些区间的和，是不是首先想到了利用「前缀和」。

但是如果 nums 会被修改呢？比如：

把第 i 个元素修改成 x
把第 i 个元素增加 x
把区间 [i, j] 内的元素都增加 x

此时，如果我们再使用「前缀和」，就没那么高效了。因为每一次更新，前缀和数组必须也随之更新，时间复杂度为 O(n)。

Yujie LiuLess than 1 minute

大端字节序（Big Endian）和小端字节序（Little Endian）

大端字节序（Big Endian）：最高有效位存于最低内存地址处，最低有效位存于最高内存处；
小端字节序（Little Endian）：最高有效位存于最高内存地址，最低有效位存于最低内存处。

endian

网络字节序

在进行网络传输的时候，先传递哪个字节？也就是说，当接收端收到第一个字节的时候，它将这个字节作为高位字节还是低位字节处理？

Yujie LiuLess than 1 minute

Springboot整合MyBatis

基本使用

首先引入相关依赖。注意版本2.x是对应springboot 2.0

<!-- Spring Boot Web 依赖 -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>

<!-- Spring Boot Test 依赖 -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-test</artifactId>
    <scope>test</scope>
</dependency>

<!-- Spring Boot Mybatis 依赖 -->
<dependency>
    <groupId>org.mybatis.spring.boot</groupId>
    <artifactId>mybatis-spring-boot-starter</artifactId>
    <version>${mybatis-spring-boot}</version>
</dependency>

<!-- MySQL 连接驱动依赖 -->
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>${mysql-connector}</version>
</dependency>

<!-- Junit -->
<dependency>
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>4.12</version>
</dependency>