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Greedy•Pattern: Greedy / Interval Scheduling•Medium

Non-overlapping intervals — minimum removal

Problem Intuition & Objective

Find the minimum number of intervals to remove so no two overlap.

Time ComplexityO(n log n)
Optimal
Space ComplexityO(1)
Memory Bounds
Optimal Algorithmic Approach

Sort by end time + greedy selection.

Core Invariants & Edge Cases

  • Sort by end time (greedy: keep interval with earliest end)
  • Greedily select intervals that don't overlap with the last selected
  • Count removed = total - kept
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