#####   ######  #####    ###    #   #  ###  #   #  ######
##  ##  ##      ##  ##  ## ##   #   #   #   #   #  ##
#####   ####    #####   #   #   #   #   #   #   #  ####
##  #   ##      ##      ## ##    # #    #    # #   ##
##   #  ######  ##       ###      #    ###    #    ######

$ curl repovive.com/roadmaps/pattern-22/intervals/meeting-rooms-ii-implementation

░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░█████████████████████████████████████████████████████████████████████████████████

#####   ######  #####    ###    #   #  ###  #   #  ######
##  ##  ##      ##  ##  ## ##   #   #   #   #   #  ##
#####   ####    #####   #   #   #   #   #   #   #  ####
##  #   ##      ##      ## ##    # #    #    # #   ##
##   #  ######  ##       ###      #    ###    #    ######

$ curl repovive.com/roadmaps/pattern-22/intervals/meeting-rooms-ii-implementation

Repovive

LeetCode 253 Meeting Rooms II - Implementation - Intervals | Pattern 22: LeetCode Interview Patterns | Repovive

Repovive.

Pattern 22: LeetCode Interview Patterns24 sections · 736 units32h total

Open in Course

LeetCode 253 Meeting Rooms II - Implementation

The approach

Separate start and end times. Sort and sweep.

def minMeetingRooms(intervals): starts = sorted(i[0] for i in intervals) ends = sorted(i[1] for i in intervals)

rooms = 0
maxRooms = 0
s = e = 0

while s < len(starts):
    if starts[s] < ends[e]:
        rooms += 1
        maxRooms = max(maxRooms, rooms)
        s += 1
    else:
        rooms -= 1
        e += 1

return maxRooms

$O(n \log n)$ time, $O(n)$ space.