Solution?
\begin{haskellcode}
addTwo :: [Int] -> [Int]
addTwo [] = []
addTwo (x:xs) = (x + 2) : addTwo xs
\end{haskellcode}
\pause
Now we want to square every element:
\pause
\begin{haskellcode}
square :: [Int] -> [Int]
square [] = []
square (x:xs) = (x * x) : square xs
\end{haskellcode}
\pause
Now we want the absolute of every element:
\begin{haskellcode}
absList :: [Int] -> [Int]
absList [] = []
absList (x:xs) = (abs x) : absList xs
\end{haskellcode}
\pause
Do you notice something?