LeetCode 435. 无重叠区间

public:
    int eraseOverlapIntervals(vector<vector<int>>& q) {
        sort(q.begin(), q.end(), [](vector<int> &a, vector<int> &b) {//传引用不然超时
            return a[1] < b[1];
        });
        if(q.empty()) return 0;
        int res = 1, r = q[0][1];//res是保留几个区间
        for(int i = 1; i < q.size(); i ++) {
            if(q[i][0] >= r) {//有等于
                res ++;
                r = q[i][1];
            }
        }
        return q.size() - res;
    }
};