Read chapters 2-5 of Skiena’s book, then do leetcode eight hours a day until your interview. Start with high-pass-rate mediums, then work your way up, and try to solve some hards. Spend about half an hour on each problem, and if you can’t think of an answer, look at the solution, reimplement it, and think hard about the underlying concepts.

This will not guarantee you a pass — honestly, some people spend months preparing for the big 5 interviews — but it may give you a fighting chance, and either way it will give you a good foundation for future interviews.