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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 units49h total

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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 $i$ (since $j$ starts after $i+1$ starts, but $i$ ends after $j$ starts).

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