Timed set

6 snippets, one planted bug in each, 20 minutes in all. There are no hints. You can run the visible tests as often as you like; the hidden tests run when the set ends. When the clock reaches 0:00 your set is submitted as it stands, so leave each snippet in its best state as you go.

• Easy snippets come first. Budget about 2, 3 and 5 minutes for easy, medium and hard ones.
• Stuck after a couple of minutes? Move on and come back; an unattempted snippet scores zero.
• Scored in interview mode: no penalty for practice mode, and a time bonus for quick fixes.

Log in to start a timed set; the hidden tests and your results are kept with your account. You can try the practice drills without one.