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$ curl repovive.com/roadmaps/data-structures/interval-trees/meeting-rooms-solution

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$ curl repovive.com/roadmaps/data-structures/interval-trees/meeting-rooms-solution

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Meeting Rooms Solution - Interval Trees | Data Structures | Repovive

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Data Structures19 sections · 729 units

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Meeting Rooms Solution

Sort and check adjacent

Sort by start time, then check if any meeting starts before the previous ends:

function canAttendMeetings(intervals)
    sort intervals by start time

    for i from 1 to length - 1
        if intervals[i].start < intervals[i-1].end then
            return false

    return true

After sorting, if no adjacent pairs overlap, then no pairs overlap at all. Why? If meeting $j$ overlaps with meeting $i$ (where $j > i + 1$ ), then meeting $i+1$ must also overlap with meeting $i$ . After sorting, intervals[i+1].start <= intervals[j].start. So if intervals[i].end > intervals[j].start, then intervals[i].end > intervals[i+1].start too.

Time: $O(n \log n)$ . Space: $O(1)$ if sorting in place.

HannahHi! I'm Hannah. Let me know if you need help understanding anything!