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Quick Summary

Model the pins and boards as a graph where any pins sharing a board are directly connected.
Check if pin1 and pin2 reside in the same connected component using BFS, DFS, or Union-Find.
Pre-build a hash map indexing each pin to its containing boards to enable efficient traversal.

What This Tests

Graph modeling and implicit graph construction
Connected components and reachability analysis
Hash-based indexing for fast neighbor lookup
Algorithmic trade-offs between traversal and disjoint set approaches

Common Patterns

Graph Traversal

BFS

Union Find

Hashing

Test Cases

Input

Output

Expected