Palantir Technologies coding interview
questions, leaked.
29 problems reported across recent Palantir Technologies 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.
Palantir's coding assessment hits you with 29 problems across a medium-heavy distribution: 16 medium, 6 hard, 7 easy. Arrays dominate the signal here, 21 of the 29 problems lean on them, so if you can't manipulate arrays fast, you're behind before you start. Hash tables, strings, and sorting back up the core pattern. You've got maybe a week to drill the top tier. If you blank mid-OA on a hash-table or two-pointer problem, StealthCoder runs invisible during screen share and surfaces a working solution in seconds. That's your hedge.
Top problems at Palantir Technologies
| # | Problem | Diff | Frequency | Pass % | Patterns |
|---|---|---|---|---|---|
| 01 | Find Beautiful Indices in the Given Array I | MEDIUM | 100.0 | 38% | Two Pointers · String · Binary Search |
| 02 | Find Beautiful Indices in the Given Array II | HARD | 92.0 | 26% | Two Pointers · String · Binary Search |
| 03 | Integer to English Words | HARD | 82.4 | 34% | Math · String · Recursion |
| 04 | Minimum Time Difference | MEDIUM | 82.4 | 62% | Array · Math · String |
| 05 | LRU Cache | MEDIUM | 80.6 | 45% | Hash Table · Linked List · Design |
| 06 | Range Sum Query - Immutable | EASY | 80.6 | 69% | Array · Design · Prefix Sum |
| 07 | Contains Duplicate II | EASY | 80.6 | 49% | Array · Hash Table · Sliding Window |
| 08 | Contains Duplicate III | HARD | 78.7 | 24% | Array · Sliding Window · Sorting |
| 09 | Contains Duplicate | EASY | 78.7 | 63% | Array · Hash Table · Sorting |
| 10 | Check If It Is a Straight Line | EASY | 78.7 | 40% | Array · Math · Geometry |
| 11 | Single Number | EASY | 78.7 | 76% | Array · Bit Manipulation |
| 12 | Maximum Size Subarray Sum Equals k | MEDIUM | 78.7 | 51% | Array · Hash Table · Prefix Sum |
| 13 | Selling Pieces of Wood | HARD | 78.7 | 52% | Array · Dynamic Programming · Memoization |
| 14 | Merge k Sorted Lists | HARD | 68.1 | 57% | Linked List · Divide and Conquer · Heap (Priority Queue) |
| 15 | Merge Intervals | MEDIUM | 64.3 | 49% | Array · Sorting |
| 16 | Shortest Word Distance III | MEDIUM | 64.3 | 59% | Array · String |
| 17 | Construct Quad Tree | MEDIUM | 59.7 | 77% | Array · Divide and Conquer · Tree |
| 18 | Count the Number of Good Subsequences | MEDIUM | 53.7 | 51% | Hash Table · Math · String |
| 19 | Minimum Equal Sum of Two Arrays After Replacing Zeros | MEDIUM | 53.7 | 50% | Array · Greedy |
| 20 | Find Players With Zero or One Losses | MEDIUM | 53.7 | 73% | Array · Hash Table · Sorting |
| 21 | Accounts Merge | MEDIUM | 45.4 | 60% | Array · Hash Table · String |
| 22 | Number of Divisible Triplet Sums | MEDIUM | 45.4 | 68% | Array · Hash Table |
| 23 | Trapping Rain Water II | HARD | 45.4 | 59% | Array · Breadth-First Search · Heap (Priority Queue) |
| 24 | All Ancestors of a Node in a Directed Acyclic Graph | MEDIUM | 45.4 | 62% | Depth-First Search · Breadth-First Search · Graph |
| 25 | Flood Fill | EASY | 45.4 | 66% | Array · Depth-First Search · Breadth-First Search |
| 26 | Number of Islands | MEDIUM | 45.4 | 62% | Array · Depth-First Search · Breadth-First Search |
| 27 | Best Time to Buy and Sell Stock | EASY | 45.4 | 55% | Array · Dynamic Programming |
| 28 | Sort List | MEDIUM | 45.4 | 62% | Linked List · Two Pointers · Divide and Conquer |
| 29 | Daily Temperatures | MEDIUM | 45.4 | 67% | Array · Stack · Monotonic Stack |
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 Palantir Technologies OA. The proctor cannot see it. Screen share cannot detect it. Built because the OA filter rejects engineers who'd pass the on-site. That's a broken filter. This is the workaround.
Get StealthCoder- array21 · 72%
- hash table8 · 28%
- string7 · 24%
- sorting7 · 24%
- breadth first search5 · 17%
- math4 · 14%
- matrix4 · 14%
- depth first search4 · 14%
- two pointers3 · 10%
- linked list3 · 10%
Arrays are the primary gating skill at Palantir, appearing in roughly 72 percent of the problem set. Prefix sums, sliding windows, and duplicate detection are all array-flavored. Hash tables (8 problems) pair closely with arrays for constraint handling and caching patterns like LRU Cache. Sorting (7 problems) shows up in merge intervals and minimum time difference. Strings (7 problems) layer in with arrays via two-pointer and rolling hash techniques. The hard tier pulls in math, dynamic programming, and divide-and-conquer, so don't sleep on those if you're targeting senior levels. Medium problems are your core grind. Drill array manipulation and hash-table collision patterns first, then lean into sorting and two-pointer logic. StealthCoder is your real-time backup when a pattern you haven't touched hits the screen during the live assessment.
Companies with similar patterns
If you prepped for Palantir Technologies, these companies recycle ~60% of the same topics.
You've seen the list.
Now make sure you pass Palantir Technologies.
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. Built because the OA filter rejects engineers who'd pass the on-site. That's a broken filter. This is the workaround. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Palantir Technologies interview FAQ
How many array problems should I solve before the Palantir OA?+
Arrays appear in 21 of 29 problems here, so this is your primary focus. Drill at least one problem each on prefix sums, sliding windows, duplicate detection, and subarray sum patterns. That covers most of what Palantir throws at you. Then shift to hash tables and sorting.
Is the medium difficulty really that heavy?+
Yes. 16 of 29 problems are medium, and problems like LRU Cache and Maximum Size Subarray Sum Equals k require both pattern recognition and design thinking under time pressure. Don't skip medium problems expecting to cruise on easy ones.
Should I study hard problems first or last?+
Last. Only 6 hard problems appear in the full set. Nail the 16 medium problems first, especially array and hash-table patterns. Hard problems like Merge k Sorted Lists pull in divide-and-conquer and heap logic, but they're not the time sink.
What two-pointer problems does Palantir actually ask?+
Find Beautiful Indices appears twice (medium and hard) and relies on two pointers plus rolling hash. That's your signal problem here. Contains Duplicate II also uses sliding window, which is two-pointer adjacent. Drill those two patterns specifically.
Do I need to know bit manipulation for this assessment?+
Single Number uses bit manipulation, but it's one of seven easy problems. It's low priority compared to arrays and hash tables. Learn XOR trick as a bonus once you're solid on the core patterns.