Hello World 对于每一个开发者来说都不陌生,因为在我们学习任何一个语言或框架的时候,都会有一个Hello World的案例来帮助我们快速入门。

如果我们使用JavaScript来输出Hello World的话,可以这样写:

alert("Hello World");

放入HTML:

<html>
<script type="text/javascript">
alert("Hello World");
</script>
</html>

在浏览器中打开就可以如下情况输出Hello World了:

挑战:仅用六种字符来编写JavaScripte

上面我们在JavaScript中实现Hello World的时候,除去HTML相关的标签和属性,上面的实现语句alert("Hello World");一共使用了13个字符,那么有没有办法用更少的字符来实现一样的功能呢?今天我们就来挑战一下:有没有办法仅使用6个字符来编写JavaScripte程序,以实现Hello World的输出?

...

...

...

先思考一下,有思路没?没思路的话,下面有提示...

...

...

...

...

...

...

...

提示:使用这六个字符:()+[]!

...

...

...

...

...

...

...

再思考一下,有思路没?没思路的话,下面有答案和解析...

...

...

...

...

...

...

...

答案

<html>
<script type="text/javascript">
[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]][([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+([][[]]+[])[+!+[]]+(![]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[])[+!+[]]+([][[]]+[])[+[]]+([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+(!![]+[])[+!+[]]]((!![]+[])[+!+[]]+(!![]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+([][[]]+[])[+[]]+(!![]+[])[+!+[]]+([][[]]+[])[+!+[]]+(+[![]]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+!+[]]]+(!![]+[])[!+[]+!+[]+!+[]]+(+(!+[]+!+[]+!+[]+[+!+[]]))[(!![]+[])[+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+([]+[])[([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+([][[]]+[])[+!+[]]+(![]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[])[+!+[]]+([][[]]+[])[+[]]+([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+(!![]+[])[+!+[]]][([][[]]+[])[+!+[]]+(![]+[])[+!+[]]+((+[])[([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+([][[]]+[])[+!+[]]+(![]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[])[+!+[]]+([][[]]+[])[+[]]+([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+(!![]+[])[+!+[]]]+[])[+!+[]+[+!+[]]]+(!![]+[])[!+[]+!+[]+!+[]]]](!+[]+!+[]+!+[]+[!+[]+!+[]])+(![]+[])[+!+[]]+(![]+[])[!+[]+!+[]])()([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]][([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+([][[]]+[])[+!+[]]+(![]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[])[+!+[]]+([][[]]+[])[+[]]+([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+(!![]+[])[+!+[]]]((!![]+[])[+!+[]]+(!![]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+([][[]]+[])[+[]]+(!![]+[])[+!+[]]+([][[]]+[])[+!+[]]+([]+[])[(![]+[])[+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+([][[]]+[])[+!+[]]+(!![]+[])[+[]]+([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+(![]+[])[!+[]+!+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+(!![]+[])[+!+[]]]()[+!+[]+[!+[]+!+[]]]+((![]+[])[+!+[]]+(![]+[])[!+[]+!+[]]+(!![]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+!+[]]+(!![]+[])[+[]]+[+!+[]]+[!+[]+!+[]+!+[]+!+[]+!+[]+!+[]]+[!+[]+!+[]+!+[]+!+[]]+(!![]+[])[+[]]+[!+[]+!+[]+!+[]+!+[]+!+[]]+[+[]]+(!![]+[])[+[]]+[!+[]+!+[]+!+[]+!+[]]+[!+[]+!+[]]+(!![]+[])[+[]]+[+!+[]]+[+!+[]]+[+[]]+(!![]+[])[!+[]+!+[]+!+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[!+[]+!+[]]+(!![]+[])[+[]]+[+!+[]]+[!+[]+!+[]+!+[]+!+[]+!+[]]+[!+[]+!+[]+!+[]+!+[]+!+[]+!+[]+!+[]]+(!![]+[])[+[]]+[!+[]+!+[]+!+[]+!+[]]+[+[]]+(!![]+[])[+[]]+[+!+[]]+[!+[]+!+[]]+[!+[]+!+[]+!+[]+!+[]+!+[]+!+[]+!+[]]+(!![]+[])[+[]]+[+!+[]]+[!+[]+!+[]+!+[]+!+[]+!+[]]+[!+[]+!+[]+!+[]+!+[]+!+[]+!+[]+!+[]]+(!![]+[])[+!+[]]+(![]+[])[!+[]+!+[]]+([][[]]+[])[!+[]+!+[]]+(!![]+[])[+[]]+[!+[]+!+[]+!+[]+!+[]]+[!+[]+!+[]]+(!![]+[])[+[]]+[!+[]+!+[]+!+[]+!+[]+!+[]]+[+!+[]])[(![]+[])[!+[]+!+[]+!+[]]+(+(!+[]+!+[]+[+!+[]]+[+!+[]]))[(!![]+[])[+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+([]+[])[([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+([][[]]+[])[+!+[]]+(![]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[])[+!+[]]+([][[]]+[])[+[]]+([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+(!![]+[])[+!+[]]][([][[]]+[])[+!+[]]+(![]+[])[+!+[]]+((+[])[([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+([][[]]+[])[+!+[]]+(![]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[])[+!+[]]+([][[]]+[])[+[]]+([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+(!![]+[])[+!+[]]]+[])[+!+[]+[+!+[]]]+(!![]+[])[!+[]+!+[]+!+[]]]](!+[]+!+[]+!+[]+[+!+[]])[+!+[]]+(![]+[])[!+[]+!+[]]+([![]]+[][[]])[+!+[]+[+[]]]+(!![]+[])[+[]]]((!![]+[])[+[]])[([][(!![]+[])[!+[]+!+[]+!+[]]+([][[]]+[])[+!+[]]+(!![]+[])[+[]]+(!![]+[])[+!+[]]+([![]]+[][[]])[+!+[]+[+[]]]+(!![]+[])[!+[]+!+[]+!+[]]+(![]+[])[!+[]+!+[]+!+[]]]()+[])[!+[]+!+[]+!+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+([![]]+[][[]])[+!+[]+[+[]]]+([][[]]+[])[+!+[]]](([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]][([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+([][[]]+[])[+!+[]]+(![]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[])[+!+[]]+([][[]]+[])[+[]]+([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+(!![]+[])[+!+[]]]((!![]+[])[+!+[]]+(!![]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+([][[]]+[])[+[]]+(!![]+[])[+!+[]]+([][[]]+[])[+!+[]]+(![]+[+[]])[([![]]+[][[]])[+!+[]+[+[]]]+(!![]+[])[+[]]+(![]+[])[+!+[]]+(![]+[])[!+[]+!+[]]+([![]]+[][[]])[+!+[]+[+[]]]+([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(![]+[])[!+[]+!+[]+!+[]]]()[+!+[]+[+[]]]+![]+(![]+[+[]])[([![]]+[][[]])[+!+[]+[+[]]]+(!![]+[])[+[]]+(![]+[])[+!+[]]+(![]+[])[!+[]+!+[]]+([![]]+[][[]])[+!+[]+[+[]]]+([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(![]+[])[!+[]+!+[]+!+[]]]()[+!+[]+[+[]]])()[([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+([][[]]+[])[+!+[]]+(![]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[])[+!+[]]+([][[]]+[])[+[]]+([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+(!![]+[])[+!+[]]]((![]+[+[]])[([![]]+[][[]])[+!+[]+[+[]]]+(!![]+[])[+[]]+(![]+[])[+!+[]]+(![]+[])[!+[]+!+[]]+([![]]+[][[]])[+!+[]+[+[]]]+([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(![]+[])[!+[]+!+[]+!+[]]]()[+!+[]+[+[]]])+[])[+!+[]])+([]+[])[(![]+[])[+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+([][[]]+[])[+!+[]]+(!![]+[])[+[]]+([][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+(![]+[])[!+[]+!+[]]+(!![]+[][(![]+[])[+[]]+(![]+[])[!+[]+!+[]]+(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+(!![]+[])[+!+[]]]()[+!+[]+[!+[]+!+[]]])())
</script>
</html>

什么?你不信这可以输出Hello World?那么你可以将其复制下来,放到HTML文件中,再打开试试吧!

为什么?

为什么我们可以仅使用这6个字符来编写这些奇奇怪怪的JavaScript代码?这完全是由于JavaScript独特的类型系统和转换机制。

上面的6个字符可以分为三类:

  • []:用于创建数组
  • !+:对数组执行一些操作
  • ():对操作进行分组

基础原理

  • []可以用来创建数组,而![]则可以返回false
  • 预定义的规则:2 + true,会转化为2 + 1,最后得到3
  • 预定义的规则:2 + "2",会转化为2 + "2",最后得到"22"

提取字母![]可以获取false![] + []那可以获取"false"字符串,那么我们就可以通过下标获取其中的字母,比如:(![] + [])[1]可以获取false字符串中第二位的字母a

提取数字![]可以获取false,由于+false可以获取0,所以+![]就可以获取到0;由于+true可以获取1,所以+!![]就可以获取到1。这样依靠运算就可以获取更多其他数字

好了,有了这些基础基础知识之后,对于这个神奇的答案知道是怎么来的了吧?

本文首发:仅用六个字符来完成Hello World,你能做到吗?,转载请注明该文章链接

参考资料

欢迎关注我的公众号:程序猿DD,获得独家整理的免费学习资源助力你的Java学习之路!另每周赠书不停哦~

仅用六种字符来完成Hello World,你能做到吗?的更多相关文章

  1. 一篇文章详解python的字符编码问题

    一:什么是编码 将明文转换为计算机可以识别的编码文本称为“编码”.反之从计算机可识别的编码文本转回为明文为“解码”. 那么什么是明文呢,首先我们从一段信息说起,消息以人们可以理解,易懂的表示存在,我们 ...

  2. Python全栈开发之路 【第三篇】:Python基础之字符编码和文件操作

    本节内容 一.三元运算 三元运算又称三目运算,是对简单的条件语句的简写,如: 简单条件语句: if 条件成立: val = 1 else: val = 2 改成三元运算: val = 1 if 条件成 ...

  3. Python2.7字符编码详解

    目录 Python2.7字符编码详解 声明 一. 字符编码基础 1.1 抽象字符清单(ACR) 1.2 已编码字符集(CCS) 1.3 字符编码格式(CEF) 1.3.1 ASCII(初创) 1.3. ...

  4. Python字符编码转换

    编码回顾 在备编码相关的课件时,在知乎上看到一段关于Python编码的回答这哥们的这段话说的太对了,搞Python不把编码彻底搞明白,总有一天它会猝不及防坑你一把.不过感觉这哥们的答案并没把编码问题写 ...

  5. Python入门之字符编码

    一.字节编码的基础知识 一.计算机基础知识 #1 我们的程序都是运行在特定的操作系统内,例如window,linux,mac等等#2 运行应用程序,需要要操作系统发出请求,我们双击运行的时候会向操作系 ...

  6. C++ tinyXML的使用和字符编码转换

    转载:http://jetyi.blog.51cto.com/1460128/761708/ 关于tinyxml使用的文档有很多(这篇文章就写的很好),这里仅提一下字符编码的转换问题,如果你不熟悉字符 ...

  7. Java第三阶段学习(三、字符流、转换流)

    一.字节流读取中文时出现的问题: 文件中有中文时,用字节流读取会出现乱码的问题,因为一个中文为两个字节. 二.字符编码表 编码表:其实就是生活中字符和计算机二进制的对应关系表. 1.ascii: 一个 ...

  8. python学习之路 三:字符编码

    本节重点 彻底掌握字符编码之前的转换关系 掌握 python2 vs python3 上编码的区别 掌握 python2 和python3 上bytes,str 的区别 补充知识点:三元运算 ​三元运 ...

  9. js控制input text字符键入/字符长度限制/字母自动大写

    功能: 1.仅允许指定字符键入 2.限制长度 实现代码: <input type="text" style="width: 6em" name=" ...

随机推荐

  1. 多线程循环打印数组 -- Java笔记

    问题描述: 现有多个长度相同的数组,现要求使用多线程将数组内的数交替打印. 如: int[] ai = {1,2,3,4,5,6,7}; String[] ac = {"A",&q ...

  2. # 095 01 Android 零基础入门 02 Java面向对象 02 Java封装 01 封装的实现 03 # 088 01 Android 零基础入门 02 Java面向对象 02 Java封装 03 封装总结 01 封装知识点总结

    095 01 Android 零基础入门 02 Java面向对象 02 Java封装 01 封装的实现 03 # 088 01 Android 零基础入门 02 Java面向对象 02 Java封装 ...

  3. 07 Sublime Text3常用快捷键

    通用常用类(General) ↑↓←→:上下左右移动光标,注意不是不是 KJHL ! Alt:调出菜单 Ctrl + Shift + P:调出命令板(Command Palette) Ctrl + ` ...

  4. 使用HTML的基本结构创建网页

    1.       网页的扩展名--html或htm 2.       如何新建网页? 步骤1: 在电脑的空白处,右键选择-->新建--文本文档 步骤2: 把txt的扩展名,改成html或htm, ...

  5. STM32F103C8T6-CubeMx串口收发程序详细设计与测试(2)——程序规划、代码编写及测试

    摘要:演示程序的功能:通过中断接收串口数据,在1750us时间内没有收到新的字节的话,将收到的数据原封不动地发送出去,以测试串口的完整收发流程.对使用到的函数进行了说明,阐述了各个函数的调用顺序和调用 ...

  6. Springboot集成logback,控制台日志打印两次,并且是不同的线程打印的

    背景 在搭建一个新项目的时候,从公司别的项目搞了个logback-spring.xml的配置过来,修改一下启动项目的时候发现 所有的日志都输出了两次 并且来自于不同的线程,猜测是配置重复了,但是仔细检 ...

  7. RHSA-2017:2299-中危: NetworkManager 和 libnl3 安全和BUG修复更新(本地提权、代码执行)

    [root@localhost ~]# cat /etc/redhat-release CentOS Linux release 7.2.1511 (Core) 修复命令: 使用root账号登陆She ...

  8. JS常见加密混淆方式

    目录 前端js常见混淆加密保护方式 eval方法等字符串参数 emscripten WebAssembly js混淆实现 JSFuck AAEncode JJEncode 代码压缩 变量名混淆 字符串 ...

  9. 每日一题 LeetCode 486. 预测赢家 【递推】【前缀和】【动态规划】

    题目链接 https://leetcode-cn.com/problems/predict-the-winner/ 题目说明 题解 主要方法:递推:动态规划:前缀和 解释说明: 求前缀和 pre_nu ...

  10. SQL学习 小知识点(一)

    这是我在做实验的时候总结的,随着学习可能会做更多的小总结 ssms上面把所有代码写下来后一块执行是行不通的(极大可能会报错),推测可能是因为ssms先对代码的语法进行了检查.    --My expe ...