learn Markdown

## 了解

#### 1.标题[数个"#" + 空格 前置]

标题会在大纲分级显示,可以跳转

记得打空格



#### 2.强调[用"**"或"__"包围]

或者选中并且使用`Ctrl` + `B`

**hello world!**



#### 3.斜体[用"*"或者"_"包围]

或者选中使用`Ctrl` + `I`

*hello world!*



***斜体＋强调:***[用"***"或者"___"包围]



#### 4.删除线[用"~~"包围]

~~Someone is addicted to play computer games.~~

#### 5.高亮[用"=="包围]

**(记得开拓展)**

==I like apples and oranges.==



#### 6.代码[用"`"包围]

 **`bool a = true`**



#### 7.代码块[``` + Enter]

```c++
#include<iostream>
using namespace std;

int main(void)
{
    cout <<"hello world!"<< endl;
    return 0;
}

> here is a dog.
>> its name is bingo.

- a cat
+ an another cat
*(its hard to use, so not be advised)

i want to do three things.
1. play vscode.
2. play vscode.
3. play vscode, too.

in c, int's upper_bound is 2^31^ - 1 = 2147483647

H~2~O~2~
H~2~O

> i want to learn markdown.
[^1]:written by Stephen Zhang.

[工头说你不是我们工地上的人](https://leetcode.cn)
[别吹牛了, 工头叫你搬砖了](https://www.neumathe.cn/#/index)

TodoList
- [ ] bilibili
- [ ] coding
- [x] sleep

| id | name | age |
| :--- | :---: | ---: |(left, mid, right)
|10086|china mobile|1|
|10010|china unicorn|2|

***
---
___
//

:sweat_smile:
:drooling_face:
:clown_face:
//

[TOC](Typora特有)

<div style = "text-align:center">
	<font style = "color : red"> i couldn't use HTML...</font>
</div>

<center>简单的文字居中也可以这样</center>

<u>you should code other programs</u>

$\LaTeX$

$a^n + b^n = c^n$

$$
%\usepackage{unicode-math}
\displaystyle \ointctrclockwise\mathcal{D}[x(t)]
\sqrt{\frac{\displaystyle3\uppi^2-\sum_{q=0}^{\infty}(z+\hat L)^{q}
\exp(\symrm{i}q^2 \hbar x)}{\displaystyle (\symsfup{Tr}\symbfcal{A})
\left(\symbf\Lambda_{j_1j_2}^{i_1i_2}\Gamma_{i_1i_2}^{j_1j_2}
\hookrightarrow\vec D\cdot \symbf P \right)}}
=\underbrace{\widetilde{\left\langle \frac{\notin \emptyset}
{\varpi\alpha_{k\uparrow}}\middle\vert
\frac{\partial_\mu T_{\mu\nu}}{2}\right\rangle}}_{\mathrm{K}_3
\mathrm{Fe}(\mathrm{CN})_6} ,\forall z \in \mathbb{R}
$$