I think Cracking the Coding Interview is very popular if you're specifically targeting interview questions. There's also the accompanying website www.careercup.com
I personally also like to do problems on hackerrank, SPOJ, or Code Jam, but are probably overkill (especially Code Jam) as they're much harder than what you probably should expect in an interview. Still, I find that it helps my nerves when I solved harder questions because then the interview questions seem much simpler so it might help you too.
I personally also like to do problems on hackerrank, SPOJ, or Code Jam, but are probably overkill (especially Code Jam) as they're much harder than what you probably should expect in an interview. Still, I find that it helps my nerves when I solved harder questions because then the interview questions seem much simpler so it might help you too.