252. Meeting Rooms

 

Given an array of meeting time intervals where intervals[i] = [starti, endi], determine if a person could attend all meetings.

 

Example 1:

Input: intervals = [[0,30],[5,10],[15,20]]
Output: false

Example 2:

Input: intervals = [[7,10],[2,4]]
Output: true

 

Constraints:

• 0 <= intervals.length <= 104
• intervals[i].length == 2
• 0 <= starti < endi <= 106

 

class Solution {
public:
    bool canAttendMeetings(vector<vector<int>>& intervals) {
        if (intervals.size() < 2) {
            return true;
        }
        sort(intervals.begin(), intervals.end(), [](auto &first, auto &second) {
            return first[0] < second[0];
        });
        
        for (int i = 1; i < intervals.size(); i++) {
            if (intervals[i][0] < intervals[i - 1][1]) {
                return false;
            }
        }
        return true;
    }
};