KLA coding interview
questions, leaked.
8 problems reported across recent KLA interviews. Top patterns: hash table, design, math. The list below is what most reported candidates actually saw, plus the honest play if you can't grind all of it.
KLA's coding assessment hits you with eight problems across a tight difficulty spread: two easy, three medium, three hard. Hash tables dominate the list, appearing in four problems, but don't sleep on design patterns and math. You'll see LRU Cache, LFU Cache, and data-stream problems that demand both algorithmic clarity and system thinking. Most candidates stumble on the hard problems or freeze mid-design question. If you blank on a cache implementation during the live OA, StealthCoder surfaces a working solution in seconds, invisible to the proctor.
Top problems at KLA
| # | Problem | Diff | Frequency | Pass % | Patterns |
|---|---|---|---|---|---|
| 01 | Maximum Product of First and Last Elements of a Subsequence | MEDIUM | 100.0 | 30% | Array · Two Pointers |
| 02 | LRU Cache | MEDIUM | 80.3 | 45% | Hash Table · Linked List · Design |
| 03 | Reaching Points | HARD | 80.3 | 34% | Math |
| 04 | Find Median from Data Stream | HARD | 70.9 | 53% | Two Pointers · Design · Sorting |
| 05 | Roman to Integer | EASY | 70.9 | 65% | Hash Table · Math · String |
| 06 | LFU Cache | HARD | 70.9 | 47% | Hash Table · Linked List · Design |
| 07 | Maximum Swap | MEDIUM | 70.9 | 52% | Math · Greedy |
| 08 | Two Sum | EASY | 70.9 | 56% | Array · Hash Table |
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 KLA OA. The proctor cannot see it. Screen share cannot detect it. Made by a working Amazon engineer who got tired of watching qualified friends bomb OAs they'd solve cold in an IDE.
Get StealthCoder- hash table4 · 50%
- design3 · 38%
- math3 · 38%
- array2 · 25%
- two pointers2 · 25%
- linked list2 · 25%
- doubly linked list2 · 25%
- sorting1 · 13%
- heap priority queue1 · 13%
- data stream1 · 13%
Hash tables are your foundation here. Four out of eight problems lean on them, often paired with linked-list manipulation or design. That means Two Sum and Roman to Integer are your warm-up, but LRU Cache and LFU Cache are where the real test lives. Math and design each show up three times, so you can't treat them as secondary. The hard problems (Reaching Points, Find Median from Data Stream, LFU Cache) mix multiple patterns together, which is why drilling them in isolation isn't enough. Study LRU Cache first to lock down the hash-table plus doubly-linked-list pattern, then move to design-heavy problems. If you hit a wall on a design problem during the OA, StealthCoder is your hedge for the live assessment.
Companies with similar patterns
If you prepped for KLA, these companies recycle ~60% of the same topics.
You've seen the list.
Now make sure you pass KLA.
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 Amazon engineer who got tired of watching qualified friends bomb OAs they'd solve cold in an IDE. Works on HackerRank, CodeSignal, CoderPad, and Karat.
KLA interview FAQ
How many hash-table problems should I solve before the KLA OA?+
Hash tables appear in 4 out of 8 problems, so treat them as your primary focus. Solve Two Sum and Roman to Integer to warm up, then spend most of your time on LRU Cache and LFU Cache. Those two will teach you the pattern that dominates KLA's list.
Is design experience enough, or do I need to grind LeetCode?+
Three problems here are design-focused (LRU Cache, LFU Cache, Find Median from Data Stream), but they all require solid implementation. You can't wing a cache design. Grind the top problems listed, especially the medium and hard design questions, to build muscle memory.
Should I study math problems first for KLA?+
Math shows up three times (Reaching Points, Roman to Integer, Maximum Swap), but two are easier. Start with hash tables and design. Math problems come later and are often harder (Reaching Points is marked hard), so tackle them once you've locked down the core patterns.
What's the ratio of easy to hard problems I'll actually see?+
KLA's pool is 25% easy, 37% medium, and 37% hard. The hard problems mix multiple topics together, so don't expect a straightforward pattern match. Drill the hard ones last, but drill them thoroughly.
Is two-pointers important for KLA, or just a bonus skill?+
Two pointers show up twice in the dataset and appear in both easy (Two Sum) and hard (Find Median from Data Stream) problems. It's not the dominant pattern, but skip it and you'll lose points on median-finding and subsequence problems. Spend 20% of prep time on it.