How do you verify answers? Say there is more than one correct answer to a solution: do you run the code in a sandbox (with memoization) to find out if it works properly? Or is there only supposed to be exactly one proper answer for each question?

EDIT You should also provide a "reset" button if I screw up the form.

EDIT The horizontal scrolling is messed up, Google Chrome 36.0.1985.143 (Official Build 287914) m on Windows. I cannot see the right two or so characters on a wide question.