Priority Queue/ Min-Heap

Priority-Queue.md

Data Structure	Leetcode Problems	Purpose	Operation
Priority Queue/Min-Heap	253. Meeting Rooms II	1.We need a way efficiently keep track of earliest ending time of meeting room we assigned already. 2.We need a efficient way to retrieve the previous meeting with earliest ending time.	1.Insert current meeting into the min-heap with key, ending time or extract assigned meeting room with earliest ending time from min-heap. It takes O(log n) time better than manually iterating on every room that’s been allocated before, O(n). 2.We compare starting time of current meeting with the topmost element in the min-heap. It only takes O(1). 3.In short, we keep all the rooms in a min heap where the key for the min heap would be the ending time of meeting.