Leetcode-meeting Rooms II

Given An array of meeting time intervals consisting of start and end Times [[s1,e1],[s2,e2],...] (Si < ei), find the minimum number of Conference rooms required.

For example,
Given [[0, 30],[5, 10],[15, 20]] ,
Return 2 .

Analysis:

It is the same with Lintcode-max number of airplanes.

Solution:

/*** Definition for a interval. * public class Interval {* int start; * int end; * Interval () {start = 0; end = 0; } * Interval (int s, int e) {start = s; end = e;} }*/ Public classSolution { Public intminmeetingrooms (interval[] intervals) {if(INTERVALS.LENGTH&LT;2)returnintervals.length; HashMap<Integer,Integer> timecounts =NewHashmap<integer,integer>();  for(Interval conf:intervals) {intStartcount = Timecounts.getordefault (conf.start,0) +1;            Timecounts.put (Conf.start,startcount); intEndcount = Timecounts.getordefault (conf.end,0)-1;        Timecounts.put (Conf.end,endcount); } List<Integer> times =NewArraylist<integer>();        Times.addall (Timecounts.keyset ());                Collections.sort (times); intMaxnum = 0, Curnum = 0;  for(inttime:times) {            intCount =Timecounts.get (time); Curnum+=count; Maxnum=Math.max (Maxnum,curnum); }        returnMaxnum; }}

Leetcode-meeting Rooms II