I would recommend 1 hour of leetcode and 1 hour of hackerrank every day, plus a 30 minute “programming koan” every morning, for 6 months leading up to when you

I would recommend 1 hour of leetcode and 1 hour of hackerrank every day, plus a 30 minute “programming koan” every morning, for 6 months leading up to when you expect the interview. You should also read “Cracking the Coding Interview” at least once.