We want to schedule interviews for N candidates. We have M intervewers who are available for interviewing candidates.

Each candidate and interviewer provides a time interval during which they are available for interviews. Find the maximum number of interviews that can be scheduled assuming each interview is 1 hour long.

The interval times are between 0 hours to 24 hours with granularity of 30 minutes. For example, the time intervals: [0, 3], [22.5, 24] are valid intervals but time intervals like: [0.7, 2] are invalid.

N < 1000 M < 1000

Input: Candidate intervals is a list of lists. The inner list is of the format: [start time, end time, candidate id] Interviewer intervals is a list of lists. The inner list is of the format: [start time, end time, interviewer id]

Output: Single integer denoting the maximum number of interviews that can be scheduled.