I'll push back against this slightly: learning what good code is requires debugging bad code, whether by way of a symbolic debugger or judicious use of printf() or breaking an algorithm down into its steps so that you can figure out its asymptotic behaviors.

I harped on checking someone's ability to debug code back when I interviewed candidates, in part because I found that people who could debug effectively could also sniff out bad code. It was something of a bonus that I also happened to select for candidates who could explain their debugging strategies and what that meant for the software they were working on.