Disjoint Set
Domain: Data Structures
🎯 Motivation
When you need to track which elements belong to the same group — connected components, network connectivity, Kruskal algorithm — disjoint sets manage merging efficiently.
📋 Concrete Example
Friends: Alice-Bob, Bob-Carol. After union operations, Alice, Bob, and Carol are in the same group. Asking find(Alice) == find(Carol) returns True.
🔗 Analogy
A school club fair. Students start alone. As they join clubs, they merge into groups. You can instantly check if two students are in the same club.