DSA Interview Revision

Revise the 40 most important DSA problems before an interview, one core pattern at a time, from arrays to dynamic programming, in five languages.

This is the bare minimum track for the days before a coding interview. It keeps one or two of the clearest problems for each pattern, so you can refresh the idea fast and move on. Every problem is judged against hidden test cases in Python, C++, Java, JavaScript and TypeScript.

What you will revise:

• Arrays, Strings and Hashing: 8 problems such as Pair That Hits the Target, No-Repeat Stretch and Flip K Zeros.
• Search, Sort and Intervals: 3 problems such as Merge the Bookings, Search the Turned Shelf and Snack Speed.
• Linked Lists, Stacks and Queues: 6 problems such as Bracket Balance, Where the Loop Begins and Biggest Bar Rectangle.
• Trees, Heaps and Greedy: 8 problems such as Longest Branch Span, Floor by Floor and Can You Reach the End.
• Backtracking and Graphs: 7 problems such as Every Subset, Count the Islands and Signal Spread Time.
• Dynamic Programming, Tries and Bits: 8 problems such as The Lone Sock, Quiet Burglar and Prefix Tree.

Solve each problem again without looking at a solution. If you get stuck on one, that pattern needs more practice, so open the matching topic track or Revquix 150 and work through more problems on it.