# Given a collection of intervals, merge all overlapping intervals.

#

# Example 1:

#

# Input: [[1,3],[2,6],[8,10],[15,18]]

# Output: [[1,6],[8,10],[15,18]]

# Explanation: Since intervals [1,3] and [2,6] overlaps, merge them into [1,6].

# Example 2:

#

# Input: [[1,4],[4,5]]

# Output: [[1,5]]

# Explanation: Intervals [1,4] and [4,5] are considered overlapping.

class Solution:

def merge(self, intervals):

intervals.sort(key=lambda x: x[0])

res = []

for interval in intervals:

if not res or res[-1][1] < interval[0]:

res.append(interval)

else:

res[-1][1] = max(res[-1][1], interval[1])

return res