Given an array of meeting time intervals consisting of start and end times [[s1,e1],[s2,e2],...] (si < ei), determine if a person could attend all meetings.

For example,

Given [[0, 30],[5, 10],[15, 20]],

return false.

1 /** 2  * Definition for an interval. 3  * struct Interval { 4  *     int start; 5  *     int end; 6  *     Interval() : start(0), end(0) {} 7  *     Interval(int s, int e) : start(s), end(e) {} 8  * }; 9  */10 class Solution {11 public:12     bool canAttendMeetings(vector
     
      & intervals) {13         sort(intervals.begin(), intervals.end(), [](const Interval &a, const Interval &b) {14             return a.start < b.start;15         });16         for (int i = 1; i < intervals.size(); ++i) {17             if (intervals[i].start < intervals[i-1].end) return false;18         }19         return true;20     }21 };
     

 

 

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.

1 /** 2  * Definition for an interval. 3  * struct Interval { 4  *     int start; 5  *     int end; 6  *     Interval() : start(0), end(0) {} 7  *     Interval(int s, int e) : start(s), end(e) {} 8  * }; 9  */10 class Solution {11 public:12     int minMeetingRooms(vector
     
      & intervals) {13         vector
      
       
        > schedule;14         for (auto interval : intervals) {15             schedule.push_back({interval.start, 1});16             schedule.push_back({interval.end, -1});17         }18         sort(schedule.begin(), schedule.end());19         int cnt = 0, res = 0;20         for (auto s : schedule) {21             if (s.second == 1) ++cnt;22             else --cnt;23             res = max(res, cnt);24         }25         return res;26     }27 };