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What happens in a DSA mock interview

You join a video call in the browser. Your interviewer explains the problem and puts the function signature and the examples on your screen. Nothing else: no story that gives away the technique, no hint hiding in the title.

Then it runs like a real coding round. You ask clarifying questions, talk through a brute force, agree on a better approach, write the code, and test it on your own edge cases. Your interviewer has the full guide beside the call: the clarifying questions a strong candidate asks, the follow-ups that separate a working answer from a good one, and what a strong answer to each sounds like.

• Minutes 0 to 5: hello, and the problem
• Minutes 5 to 45: clarify, approach, code, test
• Minutes 45 to 60: feedback, out loud, then written down

What the DSA questions cover

Pick DSA when you book and the question can come from either side of it. Difficulty follows the level on your profile, from easy warm ups to the hard end. Mark yourself as advanced and every question is a hard one.

• Data structures: arrays, linked lists, stacks and queues, trees and binary search trees, heaps, tries and graphs
• Algorithms: sorting, binary search (including binary search on the answer), two pointers, sliding window, recursion and backtracking, greedy, dynamic programming and bit manipulation

Why practise DSA with a person, not only LeetCode

Solving a problem alone and solving it while someone watches are different skills. LeetCode tells you whether the code passes. An interviewer notices that you started typing before you understood the problem, that you went quiet for four minutes, or that you never said the complexity out loud. Those are the things that decide real interviews, and they only show up when someone is listening.

How to get the most out of each round

• Think out loud from the first minute, even when you are unsure
• Ask at least two clarifying questions before writing any code
• State the brute force first, then improve it, and give the complexity of both
• Test your code on an edge case you chose, before your interviewer picks one
• Take the interviewer seat too: running a round teaches you what interviewers listen for

Some of the DSA questions you might get

A few from the bank, so you know the level. Your interviewer never tells you which one is coming.

• Two Sum (Easy)
• Longest Substring Without Repeating Characters (Medium)
• Merge Intervals (Medium)
• LRU Cache (Medium)
• Number of islands (Medium)
• Rotten Oranges (Medium)
• Top K Frequent Elements (Medium)
• Word Break (Medium)
• Longest Increasing Subsequence (Medium)
• Trapping Rainwater (Hard)
• Sliding Window Maximum (Hard)
• Minimum Window Substring (Hard)
• Median of 2 sorted arrays (Hard)
• Aggressive Cows (Hard)
• Edit distance (Hard)
• N Queen (Hard)

Frequently asked questions

Is a DSA mock interview on Practick free?

Yes. Being interviewed costs one credit and interviewing someone earns one, and every new account starts with a free credit. There is nothing to pay.

How hard are the questions?

That depends on the level on your profile. Beginners mostly get easy and medium problems, intermediate engineers a mix of all three, and advanced engineers always get a hard one.

Do I see the solution afterwards?

Yes. The model solution unlocks once the session settles, so you can compare it with your own attempt while it is still fresh.

What if I have never been interviewed before?

That is who it helps most. The first time a stranger watches you code should not be the interview that counts.

More ways to practise

• System design mock interviews: HLD rounds like Design Twitter, Uber and a rate limiter.
• SWE mock interviews: Rehearse the technical rounds of a software engineering loop, coding and design.
• Free mock interview practice: How Practick stays free, and what you get without paying anything.

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