56. Merge Intervals

# Definition for an interval.
class Interval(object):
    def __init__(self, s=0, e=0):
        self.start = s
        self.end = e

class Solution(object):
    def merge(self, intervals):
        """
        :type intervals: List[Interval]
        :rtype: List[Interval]
        """
        
        
        # Just go through the intervals sorted by start coordinate and either combine the current interval with the previous one if they overlap, or add it to the output by itself if they don‘t.
        
        res = []
        for interval in sorted(intervals, key = lambda i : i.start):
            if res and interval.start <= res[-1].end:
                res[-1].end = max(res[-1].end, interval.end)
            else:
                res.append(interval)
        return res