How do I practice coding and algorithm questions?

Use PracHub's coding console to write, test, and debug your solutions in Python or JavaScript. View hints, test against sample inputs, and compare with official solutions.

What difficulty level is this coding question?

This is a medium difficulty Coding & Algorithms question, commonly asked during Onsite rounds at Pinterest.

What role is this question designed for?

This question is commonly asked for Machine Learning Engineer candidates at Pinterest during technical interviews.

Hierarchical Access Control for an Advertising Platform

Quick Overview

This question tests practical application of graph traversal and access control system design using a directed acyclic group hierarchy. It evaluates a candidate's ability to model inheritance-based permissions, choose appropriate data structures for efficient ancestor lookups, and handle grant/revoke semantics under read-heavy workloads — core competencies in coding and algorithms interviews for roles requiring systems thinking.

medium
Pinterest
Coding & Algorithms
Machine Learning Engineer