[leetcode] 252. Meeting Rooms 解题报告

题目链接：https://leetcode.com/problems/meeting-rooms/

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.

思路：非常简单的查区间是否有重合的题目，先按照start排个序，sweep line

代码如下：

/**
 * Definition for an interval.
 * struct Interval {
 *     int start;
 *     int end;
 *     Interval() : start(0), end(0) {}
 *     Interval(int s, int e) : start(s), end(e) {}
 * };
 */
class Solution {
public:
    bool canAttendMeetings(vector<Interval>& intervals) {
        if(intervals.size() == 0) return true;
        sort(intervals.begin(), intervals.end(), [](Interval a, Interval b){ return a.start < b.start;});
        int end = intervals[0].end;
        for(int i = 1; i< intervals.size(); i++)
        {
            if(intervals[i].start < end)
                return false;
            end = intervals[i].end;
        }
        return true;
    }
};