Alibaba coding interview
questions, leaked.
5 problems reported across recent Alibaba interviews. Top patterns: array, hash table, string. The list below is what most reported candidates actually saw, plus the honest play if you can't grind all of it.
Alibaba's interview is lean but brutal. Five problems across the dataset, four at medium, one hard. You're looking at array, hash-table, and string patterns that repeat. The company doesn't waste time on warm-ups. Arrays show up in 3 of the top problems, hash-tables in another 3. If you hit a wall on their online assessment, StealthCoder runs invisible during screen-share and delivers a working solution in seconds. You won't blank. You'll have a backup.
Top problems at Alibaba
| # | Problem | Diff | Frequency | Pass % | Patterns |
|---|---|---|---|---|---|
| 01 | Path Sum IV | MEDIUM | 100.0 | 63% | Array · Hash Table · Tree |
| 02 | Split Concatenated Strings | MEDIUM | 100.0 | 43% | Array · String · Greedy |
| 03 | Split Array with Equal Sum | HARD | 100.0 | 50% | Array · Hash Table · Prefix Sum |
| 04 | Valid Parenthesis String | MEDIUM | 100.0 | 39% | String · Dynamic Programming · Stack |
| 05 | Longest Substring Without Repeating Characters | MEDIUM | 63.7 | 37% | Hash Table · String · Sliding Window |
Frequencies derived from public community-tagged interview reports. Click a row to view on LeetCode.
You have a week, maybe less. You can't out-grind the list above. StealthCoder runs invisibly during the actual Alibaba OA. The proctor cannot see it. Screen share cannot detect it. Made by an Amazon engineer who watched the leaked-problem repo become an industry secret. He decided you should have it too.
Get StealthCoder- array3 · 60%
- hash table3 · 60%
- string3 · 60%
- greedy2 · 40%
- tree1 · 20%
- depth first search1 · 20%
- binary tree1 · 20%
- prefix sum1 · 20%
- dynamic programming1 · 20%
- stack1 · 20%
The distribution is tighter than most: array, hash-table, and string each appear 3 times across the small set, meaning pattern overlap is real. Greedy appears twice. Tree and graph algorithms sit lower. The hard problem, Split Array with Equal Sum, chains array, hash-table, and prefix-sum logic. This tells you Alibaba wants candidates who can combine data structures, not just know them in isolation. Start with array manipulation and hash-table indexing. String problems lean greedy and sliding-window. The median is medium, so you need speed and accuracy on mid-range complexity. StealthCoder is your safety net if you encounter a collision between multiple patterns during the live assessment.
Companies with similar patterns
If you prepped for Alibaba, these companies recycle ~60% of the same topics.
You've seen the list.
Now make sure you pass Alibaba.
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 an Amazon engineer who watched the leaked-problem repo become an industry secret. He decided you should have it too. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Alibaba interview FAQ
Should I study trees first for Alibaba, or arrays?+
Arrays. They appear in 3 of the top 5 problems, hash-tables in another 3. Tree problems show up once. Drill array traversal, two-pointer logic, and prefix-sum patterns first. Trees are lower frequency here.
Is greedy algorithm knowledge required for Alibaba?+
Yes, but secondary. Greedy appears in 2 problems, both string-related: Split Concatenated Strings and Valid Parenthesis String. It's paired with other patterns. You need greedy intuition, but it's not the core demand.
What's the hardest problem I'll face?+
Split Array with Equal Sum. It's the only hard problem and combines array partitioning, hash-tables for index tracking, and prefix-sum optimization. It's the one problem that tests if you can chain multiple techniques.
How much time should I spend on sliding-window?+
It appears in one problem: Longest Substring Without Repeating Characters. Sliding-window is essential for that one, but low frequency overall. Get the pattern solid, then move to array and hash-table drills.
Can I skip dynamic programming for Alibaba?+
It appears once, in Valid Parenthesis String, paired with greedy and stack. Don't skip it entirely, but it's not a primary focus. Array and hash-table competence matters far more to your success.