Palantir Software Engineer Onsite Coding Questions
14+ questions from real Palantir Software Engineer Onsite Coding rounds, reported by candidates who interviewed there.
What does the Palantir Onsite Coding round test?
The Palantir onsite coding round is the core technical evaluation. Software Engineer candidates typically see 2-3 algorithm and data structure problems. Problems range from medium to hard difficulty, and interviewers evaluate both correctness and code quality.
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Palantir Software Engineer Onsite Coding Questions
During the Palantir virtual onsite, I failed to complete the technical assessment within the time limit. I pursued an overly complex approach instead of a standard recursive solution, which prevented
Should I read into this rejection email?
This was the rejection email I got after the final round palantir internship interviews. I thought that all of the technical, decomp and learnings interviews went really well and I got on really well
Palantir virtual-onsite learning interview
Has anyone gone through the virutal-onsite at Palantir before? I would like to know what kind of questions were asked in the learning segment of the interview. How does one even prepare for this? The
Palantir HM Round What to Expect?
Hi everyone, I have a the final HM round for palantir for their new grad fdse role. I was wondering if anyone has gone through that process and has any tips for it. I heard they do reject a lot after
LeetCode #3006: Find Beautiful Indices in the Given Array I. Difficulty: Medium. Topics: Two Pointers, String, Binary Search, Rolling Hash, String Matching, Hash Function. Asked at Palantir in the last 6 months.
#443 String Compression
LeetCode #443: String Compression. Difficulty: Medium. Topics: Two Pointers, String. Asked at Palantir in the last 6 months.
LeetCode #244: Shortest Word Distance II. Difficulty: Medium. Topics: Array, Hash Table, Two Pointers, String, Design. Asked at Palantir in the last 6 months.
LeetCode #1202: Smallest String With Swaps. Difficulty: Medium. Topics: Array, Hash Table, String, Depth-First Search, Breadth-First Search, Union-Find, Sorting. Asked at Palantir in the last 6 months.
Palantir Software Engineer Intern Interview - Onsite (Decomp/Learning)
I recently had my coding interview with them and now got moved to the virtual onsite. It is 2 back to back interviews. Does anyone have any tips for the decomposition / live learning rounds? If anyone
Palantir Decomp/Learning Interview
Hi Everyone, I have the palantir virtual onsite coming up and it's two interview which are their decomp and learning interviews. I was wondering if any of you guys had any insight on what to expect fr
Just wondering how many are waiting for either an interview (onsite, HM interview) or an offer for Palantir’s Path program
Access Control Tree: Permission Inheritance and Overrides in a Hierarchical Resource Tree
## Problem You have a tree of resources (like a file system). Each node can have explicit permissions set for users. If a node has no explicit permission for a user, it inherits from its parent. An explicit `DENY` always overrides an inherited `ALLOW`. Implement: ```python class AccessControlTree: def __init__(self): ... def add_node(self, node_id: str, parent_id: str | None) -> None: ... def set_permission(self, node_id: str, user: str, perm: str) -> None: # perm: "ALLOW"|"DENY" def can_access(self, node_id: str, user: str) -> bool: ... ``` ## Example ``` tree.add_node("root", None) tree.add_node("docs", "root") tree.add_node("secret", "docs") tree.set_permission("root", "alice", "ALLOW") tree.set_permission("secret", "alice", "DENY") tree.can_access("docs", "alice") -> True # inherits from root tree.can_access("secret", "alice") -> False # explicit DENY overrides tree.can_access("root", "bob") -> False # no permission set anywhere ``` ## Follow-ups 1. How does your traversal strategy change if the tree is very deep (10,000+ levels)? 2. What if a user can belong to multiple groups, each with their own permissions? 3. How would you batch-evaluate access for 1,000 users across 500 nodes efficiently?
Palantir SWE Onsite - Anagram Dictionary
## Problem Group a list of words into anagram clusters, returning a dictionary mapping sorted keys to word lists. ## Likely LeetCode equivalent Directly matches Group Anagrams (LC 49). ## Tags hash_table, strings, sorting, palantir
## Problem Design a spatial index that supports storing 2D points and efficiently answering proximity queries. Implement: ```python class SpatialIndex: def insert(self, point_id: str, x: float, y: float) -> None: ... def delete(self, point_id: str) -> None: ... def nearest(self, x: float, y: float, k: int) -> list[str]: ... def range_query(self, x1: float, y1: float, x2: float, y2: float) -> list[str]: ... ``` `nearest` returns the `k` closest point IDs by Euclidean distance. `range_query` returns all points within the given bounding box. ## Example ``` index.insert("A", 1.0, 2.0) index.insert("B", 3.0, 4.0) index.insert("C", 1.5, 2.5) index.nearest(1.0, 2.0, k=2) -> ["A", "C"] # closest two to (1,2) index.range_query(0, 0, 2, 3) -> ["A", "C"] # within bounding box ``` ## Follow-ups 1. Compare a grid-bucket approach vs. a k-d tree for this workload. When does each win? 2. How do you handle points clustered in a small area causing one bucket to dominate? 3. What changes if points are moving (e.g., tracking vehicles in real time)? 4. How would you scale this index to billions of points across multiple machines?
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