Greedy / Heap•Pattern: Greedy + Heap•Medium

Meeting rooms II — minimum rooms needed

Problem Intuition & Objective

Find the minimum number of conference rooms to hold all meetings.

Time ComplexityO(n log n)

Optimal

Space ComplexityO(n)

Memory Bounds

Optimal Algorithmic Approach

Sort + min-heap of room end times.

Sort meetings by start time
Min-heap of end times: if next start >= min end, reuse room (pop and push new end)
Otherwise allocate a new room (push new end); heap size = rooms used

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