>Puzzle 122. Let C be the free category on this graph:

>

>Let's use this as a database schema. Draw an example of a database built using this schema. Mathematically it's a functor F:C→Set. But what does this mean in concrete terms? You can draw it as a table, like you would see in a spreadsheet.

Giving an instance to the above free-category \\(C\\), just produces something that looks like a 2 column table,

\\[
\begin{array}{c|c}
\text{People} & \mathrm{FriendOf} \\\\
\hline
Alice & Bob \\\\
Bob & Alice \\\\
\vdots & \vdots \\\\
Stan & Tyler \\\\
Tyler & Stan. \\\\
\vdots & \vdots
\end{array}
\\]