Coding Interview Countdown
Enter the weeks until your interview and the hours you can study each week, and get a spaced, topic-by-topic plan across the core data-structures and algorithms — review week included.
A plan beats a pile of problems
Most interview prep stalls because it has no shape — you grind random problems, over-study the topics you already know, and run out of time on the ones you don’t. Spacing the core topics across the weeks you actually have, and leaving room at the end for timed review, keeps the preparation honest and reduces the last-week panic.
When you reach the algorithms themselves, the Big-O Complexity Estimator is a quick way to sharpen the scaling intuition interviewers probe for.
Frequently Asked Questions
How does the study plan decide what to cover each week?
It spreads twelve core topics — arrays and strings, hashing, two pointers and sliding window, stacks and queues, linked lists, trees and BSTs, graphs and traversal, heaps, sorting and searching, recursion and backtracking, dynamic programming, and system-design basics — evenly across your study weeks. When you have three weeks or more, the final week is reserved for review and mock interviews so you consolidate rather than cram new material at the end.
How many weeks and hours should I plan for?
It depends on your starting point. A refresher for an experienced engineer can fit in three to four weeks at a few hours a night; a first serious attempt at data-structures interviews is more comfortable over eight to twelve weeks. The tool works from whatever you give it — enter your real availability rather than an aspirational number you won't keep, and adjust as you go.
Should I really study one topic per block?
Grouping practice by topic early on builds pattern recognition faster than random problems, because you see the same idea from several angles in a row. As the interview approaches, mix topics and do timed sets under interview conditions — that is what the review week is for. The plan gives you the structure; the practice problems themselves come from your problem set of choice.
Is a topic plan enough to pass?
It is a scaffold, not a guarantee. Passing also needs consistent problem-solving practice, saying your reasoning out loud, and mock interviews to handle nerves and communication. Treat the plan as a way to make sure nothing important is skipped, and pair it with real, spaced repetition of problems.
A suggested study scaffold, not a guarantee of results. Pair it with consistent problem practice and mock interviews.