Interview Intel · Ozon

Ozon coding interview
questions, leaked.

14 problems reported across recent Ozon interviews. Top patterns: array, string, hash table. The list below is what most reported candidates actually saw, plus the honest play if you can't grind all of it.

Founder's read

Ozon's coding assessment is mostly beginner-friendly. Out of 14 total problems, 9 are easy, 4 are medium, and only 1 is hard. Arrays dominate the test (6 problems), followed by strings (4) and hash tables (3). You'll see Two Sum, Valid Parentheses, Merge Intervals, and Longest Substring Without Repeating Characters in rotation. The bar is low on difficulty, but speed matters. If you hit a wall on the live assessment, StealthCoder runs invisibly and solves it in seconds so you don't lose time.

Tracked problems
14
Easy
9/ 64%
Medium
4/ 29%
Hard
1/ 7%

Top problems at Ozon

leaked_problems.csv14 rows
#ProblemDiffFrequency
01Valid ParenthesesEASY
100.0
02Merge IntervalsMEDIUM
91.8
03Squares of a Sorted ArrayEASY
91.8
04Monotonic ArrayEASY
86.4
05Department Top Three SalariesHARD
86.4
06Two SumEASY
79.4
07Move ZeroesEASY
69.5
08Reverse Linked ListEASY
69.5
09Invert Binary TreeEASY
69.5
10First Unique Character in a StringEASY
69.5
11Best Time to Buy and Sell StockEASY
69.5
12Decode StringMEDIUM
69.5
13Department Highest SalaryMEDIUM
69.5
14Longest Substring Without Repeating CharactersMEDIUM
69.5

Frequencies derived from public community-tagged interview reports. Click a row to view on LeetCode.

The hedge

You have a week, maybe less. You can't out-grind the list above. StealthCoder runs invisibly during the actual Ozon OA. The proctor cannot see it. Screen share cannot detect it. Made by a working FAANG engineer who treats the OA the way companies treat hiring: as a game with rules you should know.

Get StealthCoder
Topic distribution
What this means

Array manipulation is the core of Ozon's screening. You need to own simple patterns: two-pointer sweeps (Move Zeroes, Squares of a Sorted Array), basic sorting (Merge Intervals), and hash-table lookups (Two Sum, First Unique Character). String problems lean on stacks and hash tables for counting. The one hard problem, Department Top Three Salaries, is a database query. Don't overstudy trees or graphs. Spend your prep time on array and string drills, because that's where you'll spend 70% of the OA. StealthCoder is your hedge for any edge case you didn't catch in practice.

Companies with similar patterns

If you prepped for Ozon, these companies recycle ~60% of the same topics.

The honest play

You've seen the list. Now make sure you pass Ozon.

Memorizing every problem above in a week is a fantasy. StealthCoder is the hedge: an AI overlay that's invisible during screen share. It reads the problem on screen and surfaces a working solution in under 2 seconds. Made by a working FAANG engineer who treats the OA the way companies treat hiring: as a game with rules you should know. Works on HackerRank, CodeSignal, CoderPad, and Karat.

Ozon interview FAQ

How many array problems should I solve before Ozon?+

Ozon has 6 array problems out of 14 total. Practice at least 10 to 15 array drills covering two-pointer, sorting, and hash-table lookup patterns. Your weakest pattern here will show up on the live assessment.

Do I need to study trees and graphs for Ozon?+

Minimal. The dataset shows only 1 tree problem and 1 each of DFS and BFS. Spend 80% of your time on arrays and strings, then pick up tree basics if you have leftover prep time.

Is the database problem worth studying?+

It's 1 hard problem out of 14. If you're weak on SQL, skip it for now and own the 13 easy and medium problems instead. The hard problem is not a gatekeeper.

What string topics come up most in Ozon assessments?+

Hash tables and stacks. Valid Parentheses, First Unique Character, Decode String, and Longest Substring Without Repeating Characters all use these patterns. Drill sliding windows and character-count logic.

How much time should I spend on sorting and two-pointers?+

They appear together in 2 to 3 problems. Practice Merge Intervals, Squares of a Sorted Array, and Move Zeroes until you can code them in under 5 minutes each. Speed here buys you buffer time on harder problems.

Problem frequencies sourced from public community-maintained interview-report repos. Problems, ratings, and trademarks are property of LeetCode and Ozon. StealthCoder is not affiliated with Ozon.