# PlayGround

## Outliner

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Some other syntax.

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## MathJax

$a^2 + b^2 = c^2$

$$\frac{d}{dx}\left( \int_{0}^{x} f(u)\,du\right)=f(x)$$

\begin{align*} e^x & = 1 + x + \frac{x^2}{2} + \frac{x^3}{6} + \cdots \\ & = \sum_{n\geq 0} \frac{x^n}{n!} \end{align*}

## Wrap

Learn about the special kinds of content on this site.

The tip box typically holds helpful information.

important information for readers who may have a direct stake.

imparts information intended to help readers avoid trouble.

## Code Blocks

This is text is indented by two spaces.
This is preformatted code all spaces are preserved:  like              <-this
/**
* The HelloWorldApp class implements an application that
* simply displays "Hello World!" to the standard output.
*/
class HelloWorldApp {
public static void main(String[] args) {
System.out.println("Hello World!"); //Display the string.
}
}

Excalibur

EA

## Diagram

 Saber 维基 CCC
 root 1st branch (see Branch) 2nd branch (very important branch)