[Leetcode] Meeting Rooms I and II

LC link1
Sort based on start time and check conflicts
1. Line 7,8 old drill, valid inputs
2. Line 10, sort element in place based on object's attribute  python programming sugar
3. Line 12, how to handle the case where len(intervals) == 1
                   Use for i in xrange( 1, len(intervals)) It will ignore the case where len(intervals) == 1

LC link
Create sorted start/end list, use rooms/end_pointer trick to iterate through

1. Line 20, should be smaller, cuz start time == end time, it means a room is released
2. Line 20, don't forget to use end_pointer
3. Line 22, 23,   it means a new room is release, don't need a new room, but move end_pointer