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Sorting•Pattern: Sorting + Greedy•Medium

Merge intervals

Problem Intuition & Objective

Merge all overlapping intervals from a list.

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

Sort + linear scan.

Core Invariants & Edge Cases

  • Sort intervals by start time
  • Compare each interval's start with the last merged interval's end
  • If overlapping, extend the end; otherwise push a new interval
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