Topological Sort

Topological sort orders the nodes of a directed acyclic graph so every edge points forward — the valid sequence for tasks with dependencies. Use it for build orders, course schedules, and any 'do A before B' problem; it also detects cycles.

4 LeetCode problems solved with the Topological Sort pattern. Practice them with spaced repetition so the pattern sticks.

• Alien DictionaryHARD · O(C)
• Build a Matrix With ConditionsHARD · O(k + R + C)
• Course ScheduleMEDIUM · O(V + E)
• Course Schedule IIMEDIUM · O(V + E)