Untitled

You are given an array of meetings where meetings[i] = [startTime, endTime, roomCapacity]. 
Each meeting will take place during the inclusive time interval [startTime, endTime] and requires 
a room with at least roomCapacity people capacity.

Return the minimum number of rooms needed to hold all meetings.

Example:
Input: meetings = [[1,4,2], [2,5,3], [3,6,2], [4,7,1]]
Output: 2

Explanation: 
- Meeting 1: [1,4] needs capacity 2
- Meeting 2: [2,5] needs capacity 3 (can't use same room as Meeting 1)
- Meeting 3: [3,6] needs capacity 2 (can use same room as Meeting 1 after it ends)
- Meeting 4: [4,7] needs capacity 1 (can use same room as Meeting 1)