Java: Meeting Rooms

Difficulty Level: HARD

Problem Statement:

You are given an array of meeting time intervals “intervals” where “intervals[i] = [ start[i], end[i] ]”, return the minimum number of conference rooms required.

Input:

intervals = [[0,30],[5,10],[15,20]]

Output:

2
Meeting one can be done in conference room 1 form 0 – 30.
Meeting two can be done in conference room 2 form 5 – 10.