Meeting Rooms III

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Leetcode

Medium

Heaps

Ordered Structures

Arrays

Google

Amazon

Microsoft

Meeting Rooms III

Schedule meetings across rooms and report which room hosts the most meetings when rooms become available at different times.

Acceptance 100%

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Problem Statement

You are given a set of meeting requests, each with a start time and an end time. There are n meeting rooms labeled from 0 to n - 1.

A meeting is assigned to the smallest-index room that is free at its scheduled start time. If no room is free, the meeting is delayed until the earliest room becomes available, and it keeps the same duration.

After all meetings are processed, return the index of the room that hosted the most meetings. If multiple rooms hosted the same maximum number, return the smallest index among them.

Input Format

n: number of meeting rooms
meetings: array of [start, end] pairs

Output Format

Return the index of the room that hosted the most meetings.

Constraints

1 <= n
meetings.length >= 1
Each meeting has start < end
Meeting times are integers and can be processed in chronological order

Hints

Sort meetings by start time.
Track free rooms by smallest index.
Track occupied rooms by earliest finishing time, and free rooms when their meetings end.
When a meeting is delayed, preserve its duration.

Input Format

An integer n.
A list of meeting intervals meetings, where each interval is [start, end].

Output Format

Return a single integer: the room index with the highest meeting count, breaking ties by smaller index.

Constraints

Assign each meeting to the lowest-index available room.
If no room is available, delay the meeting to the earliest time a room frees up.
Preserve meeting duration when delayed.

Examples

Sample cases returned by the problem API.

Example 1

Input

n = 2
meetings = [[0,10],[1,5],[2,7],[3,4]]

Output

Explanation

Room 0 takes the first meeting. Room 1 takes the second. The third meeting is delayed until room 1 frees up, and the fourth meeting is also delayed. In the end, room 0 hosts more meetings than room 1.

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