Tag
graph
Coding
Plant Infection on a Grid: Spread, Recovery, Death, and Firebreaks
Five escalating grid questions, from multi-source BFS to timed events and an exact firebreak planner, with Java and Python solutions.
Coding
Design a Versioned Social Graph with Snapshots
Use logical time and edge-activity intervals to support O(1) snapshots, historical following queries, friend recommendations, and snapshot diffs.