```pseudocode
% This quicksort algorithm is extracted from Chapter 7, Introduction to Algorithms (3rd edition)
\begin{algorithm}
\caption{Quicksort}
\begin{algorithmic}
\PROCEDURE{Quicksort}{$$A, p, r$$}
    \IF{$$p < r$$}
        \STATE $$q = $$ \CALL{Partition}{$$A, p, r$$}
        \STATE \CALL{Quicksort}{$$A, p, q - 1$$}
        \STATE \CALL{Quicksort}{$$A, q + 1, r$$}
    \ENDIF
\ENDPROCEDURE
\PROCEDURE{Partition}{$$A, p, r$$}
    \STATE $$x = A[r]$$
    \STATE $$i = p - 1$$
    \FOR{$$j = p$$ \TO $$r - 1$$}
        \IF{$$A[j] < x$$}
            \STATE $$i = i + 1$$
            \STATE exchange
            $$A[i]$$ with $$A[j]$$
        \ENDIF
        \STATE exchange $$A[i]$$ with $$A[r]$$
    \ENDFOR
\ENDPROCEDURE
\end{algorithmic}
\end{algorithm}
```

Generates:

% This quicksort algorithm is extracted from Chapter 7, Introduction to Algorithms (3rd edition)
\begin{algorithm}
\caption{Quicksort}
\begin{algorithmic}
\PROCEDURE{Quicksort}{$$A, p, r$$}
    \IF{$$p < r$$}
        \STATE $$q = $$ \CALL{Partition}{$$A, p, r$$}
        \STATE \CALL{Quicksort}{$$A, p, q - 1$$}
        \STATE \CALL{Quicksort}{$$A, q + 1, r$$}
    \ENDIF
\ENDPROCEDURE
\PROCEDURE{Partition}{$$A, p, r$$}
    \STATE $$x = A[r]$$
    \STATE $$i = p - 1$$
    \FOR{$$j = p$$ \TO $$r - 1$$}
        \IF{$$A[j] < x$$}
            \STATE $$i = i + 1$$
            \STATE exchange
            $$A[i]$$ with $$A[j]$$
        \ENDIF
        \STATE exchange $$A[i]$$ with $$A[r]$$
    \ENDFOR
\ENDPROCEDURE
\end{algorithmic}
\end{algorithm}

To use display mode, again surround your expression with $$ and place it as a separate paragraph. Here is an example:

You can also use \begin{equation}...\end{equation} instead of $$ for display mode math. MathJax will automatically number equations:

\begin{equation} \label{eq:cauchy-schwarz} \left( \sum_{k=1}^n a_k b_k \right)^2 \leq \left( \sum_{k=1}^n a_k^2 \right) \left( \sum_{k=1}^n b_k^2 \right) \end{equation}

and by adding \label{...} inside the equation environment, we can now refer to the equation using \eqref.

Note that MathJax 3 is a major re-write of MathJax that brought a significant improvement to the loading and rendering speed, which is now on par with KaTeX.

```c++
code code code
```

int main(int argc, char const \*argv[])
{
    string myString;

    cout << "input a string: ";
    getline(cin, myString);
    int length = myString.length();

    char charArray = new char * [length];

    charArray = myString;
    for(int i = 0; i < length; ++i){
        cout << charArray[i] << " ";
    }

    return 0;
}

For displaying code in a list item, you have to be aware of the indentation, as stated in this FAQ. You must indent your code by (3 * bullet_indent_level) spaces. This is because kramdown (the markdown engine used by Jekyll) indentation for the code block in lists is determined by the column number of the first non-space character after the list item marker. For example:

1. We can put fenced code blocks inside nested bullets, too.

   1. Like this:

      ```c
      printf("Hello, World!");
      ```

   2. The key is to indent your fenced block in the same line as the first character of the line.

Which displays:

1. We can put fenced code blocks inside nested bullets, too.

   1. Like this:

      printf("Hello, World!");
      

   2. The key is to indent your fenced block in the same line as the first character of the line.

By default, it does not display line numbers. If you want to display line numbers for every code block, you can set kramdown.syntax_highlighter_opts.block.line_numbers to true in your _config.yml file.

If you want to display line numbers for a specific code block, all you have to do is wrap your code in a liquid tag:

{% highlight c++ linenos %}
code code code
{% endhighlight %}

The keyword linenos triggers display of line numbers. Produces something like this:

1
2
3
4
5
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7
8
9
10
11
12
13
14
15
16
17
18
int main(int argc, char const \*argv[])
{
string myString;

    cout << "input a string: ";
    getline(cin, myString);
    int length = myString.length();

    char charArray = new char * [length];

    charArray = myString;
    for(int i = 0; i < length; ++i){
        cout << charArray[i] << " ";
    }

    return 0;

}