#class Interval:
#  def __init__(self, start, end):
#    self.start = start
#    self.end = end

#  def print_interval(self):
#    print("[" + str(self.start) + ", " + str(self.end) + "]", end='')

class Solution:
  def merge(self, intervals):
    result = []

    # sort the intervals in-order to merge them
    intervals.sort(key = lambda i: i.start)
    
    for interval in intervals:
      if not result: 
        result.append(interval)
      else:
        # [a, b] is the previous interval in the result array
        # [c, d] is the current internal from the loop
        a, b = result[-1].start, result[-1].end
        c, d = interval.start, interval.end
        # if overlap
        if c <= b:
          # merge then update the result array
          merged = Interval(a, max(b, d))
          result[-1] = merged
        else:
          # just add the new interval
          result.append(interval)
      
    return result