I've had folks who just jump into the code without any planning. It usually bites them about 20-30 minutes in. On the other hand, I remember one guy who spent the first 20 minutes planning and only 40 coding and ended up doing better than most.
The point here is not "Write as many lines of code as you can". I want the candidate to plan - it's a crucial part of the job. FizzBuzz, sorts and the like don't require much planning. Minesweeper does.
The point here is not "Write as many lines of code as you can". I want the candidate to plan - it's a crucial part of the job. FizzBuzz, sorts and the like don't require much planning. Minesweeper does.