Grokking 75: Top Coding Interview Questions

It is a curated set of 75 coding interview questions spread across 18 topic areas, each with its own solution lesson containing the approach, a step by step algorithm, a walkthrough, code in six languages, and the complexity analysis. It is built for coverage: the point is that finishing it leaves no obvious hole in your preparation.

Anyone short on time before an interview. If you have three or four weeks rather than three or four months, a curated 75 beats grinding a problem bank at random, because the selection is doing work for you that you cannot do for yourself until after you have already learned the material.

Arrays and strings, two pointers, sliding window, matrix, hash maps and sets, linked lists, stacks and monotonic stacks, tree depth first search, tree breadth first search, binary trees, graphs, graph breadth and depth first search, heaps and priority queues, backtracking, dynamic programming, intervals, divide and conquer, and tries.

Grokking the Coding Interview is the full curriculum: 42 patterns and more than 300 problems, built to teach you pattern recognition from scratch. This is the short list, organised by topic rather than by pattern, for people who need coverage quickly. If you have months, take the patterns course. If you have weeks, take this one. If you have months and you are anxious, take the patterns course and use this as the final revision pass.

It is enough to be dangerous rather than enough to be comfortable, and that is an honest trade. Seventy-five well chosen problems across 18 topics will expose you to every common shape at least once, which is far better preparation than 300 problems all drawn from four topics you already liked. If you have more time, more practice will help, but this is the highest return per hour on the list.

Python, Java, C++, JavaScript, Go, and C#. Every solution is given in all six.

You should already know your basic data structures: arrays, hash maps, linked lists, trees, and graphs. This course practises them rather than teaching them. If those are shaky, Grokking Data Structures and Algorithms for Coding Interviews is the better starting point, and this becomes the revision pass afterwards.

A topic at a time rather than in a straight line, and attempt each problem before opening its solution. The single biggest mistake with a curated list is reading it, because the solutions are clear enough that everything looks obvious in the moment and none of it survives to the interview.

Text-based, with runnable code for every solution. That is the right shape for practice: you attempt, run, fail, and reread the walkthrough, which is a loop you want to control yourself rather than watch.

Yes. Design Gurus issues a certificate once you have completed the course, and you can share the link directly or add it to your LinkedIn profile.