Markdown 示例

其它

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https://www.cnblogs.com/Iowa-Battleship/p/9670741.html
https://blog.csdn.net/fzch_struggling/article/details/44998901
矩阵：http://blog.csdn.net/bendanban/article/details/44221279

$\varphi \phi \psi\underline{\space}\geqslant\leqslant\geq\leq\ qwq\ \leftarrow\gets\rightarrow\to\leftrightarrow\ \Leftarrow\Rightarrow\Leftrightarrow$

$$A+B\xrightarrow[170^{\circ}]{qwq}C\uparrow$$

1. $$\color{white}{\boxed{\color{red}{attack\ is\ our\ red\ sun}}}$$
2. $\bigcup_{i=1}^na_i$（所有数$or$） $\cup\bigcup\Cup\cap\bigcap\Cap\setminus\notin\emptyset\varnothing\neg p \lor\land\therefore\ \because$
   子集：$\subseteq \nsubseteq \supseteq \nsupseteq$
3. $\mathfrak{abcdABCD}$ $\text{这是文字}$ $\color{red}{2333\pm}$
4. $\color{black}{\text{m}}\color{red}{\text{jt}}\ \text{orz}\ \mathbb{orz}$
5. $\mathscr{THE\ END}\ \mathcal{THE\ END}\ \mathsf{THE\ END}\ \mathrm{THE\ END}\ \mathit{THE\ END}\ $
6. $(x+1)^2=\class{hidden}{(x+1)(x+1)}$
7. $\vec a$ $\vec {MN}$ $\overrightarrow {MN}$
8. $\infty\ \binom{n}{k}\ {n\brace m}\ {n\choose m}$ $\displaystyle\infty\ \binom{n}{k}\ {n\brace m}\ {n\choose m}$
9. $\overbrace{1+2+\cdots+100^{\circ}\circ}$
10. $\underbrace{1+2+\cdots+100}$
11. $\begin{matrix}\underbrace{1+2+\cdots+100}\\5050\end{matrix}$
12. $$f(n)\underline{XXX}\leftrightarrow\Leftrightarrow\overline{YYY\underline{ZZZ}}$$
13. $$ax\equiv b\ mod\ p\\\Downarrow\\ ax-kp=b$$
14. $$\int_a^bf(x)dx\approx\frac{b-a}{6}\left[f(a)+f(b)+4f(\frac{a+b}{2})\right]$$
15. $$\begin{Bmatrix}n\\k \end{Bmatrix}=\begin{Bmatrix}n-1\\k-1\end{Bmatrix}+k\cdot \begin{Bmatrix}n-1\\k \end{Bmatrix}\\ \begin{bmatrix}n\\k \end{bmatrix}=\begin{bmatrix}n-1\\k-1 \end{bmatrix}+(n-1)\cdot \begin{bmatrix}n-1\\k \end{bmatrix}$$
16. 
    $$A=\left[ \begin{matrix} 4 & -5\\-2 & 3 \end{matrix} \right],\ b=\left[ \begin{matrix} -13\\9 \end{matrix} \right] \tag{1}$$
    $$A=\left[ \begin{matrix} a_{11} & a_{12} & \cdots & a_{1m}\\ a_{21} & a_{22} & \cdots & a_{2m}\\ \vdots & \vdots & \ddots & \vdots\\ a_{n1} & a_{n2} & \cdots & a_{nm} \end{matrix} \right] \tag{2}$$
    $$\begin{pmatrix} 1&2&3\\2&3&4\\5&6&7 \end{pmatrix}=\begin{vmatrix} 1&2&3\\a&b&c\\5&6&7 \end{vmatrix}+\left(\begin{bmatrix} 1&2&3\\d&e&f\\5&6&7 \end{bmatrix}\right)$$
    $$rank(A^*)= \begin{cases} n,& rank(A)=n\\ 1,& rank(A)=n-1\\ 0,& rank(A)<n-1 \end{cases}$$
    array中lcr表示各列内容的居左、居中、居右。
    $$\left\{ \begin{array}{c} x=&eq\\ y=&eq2 \end{array} \right.$$
    $$\begin{equation} \left\{ \begin{array}{c} x&=eq1\\ y&=eq2 \end{array} \right. \end{equation}$$
17. 表格

默认列左对齐	右对齐	中间对齐
计算机	$1600	5
手机	$12	12
管线	$1	234

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$$\begin{aligned}S(x)&=\sum_{i=1}^ndis(x,i)^K\\&=\sum_{i=1}^n\sum_{k=0}^{dis(x,i)}S(K,k)\cdot k!\cdot \binom{dis(x,i)}{k}\\&=\sum_{i=1}^n\sum_{k=0}^KS(K,k)\cdot k!\cdot \binom{dis(x,i)}{k}\\&=\sum_{k=0}^KS(K,k)\cdot k!\cdot\sum_{i=1}^n\binom{dis(x,i)}{k}\end{aligned}$$