[blackysky]

You should comment your code if and only if your algorithms has special pre-conditions and post-conditions otherwise your choice of variables name should make your code speak by itself... exemple of pre condition: your algorithm don't handle non latin word ... exemple of post condition , your algorithm only return a specific format like aa-bb-cc ...

or like my teacher said use your common sense, make your code as clear as possible.. I should understand it without you ...