Merge Intervals

0Medium

Merge Intervals

Given an array of intervals, merge all overlapping intervals and return an array of non-overlapping intervals covering all input intervals.

Example 1:

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

Example 2:

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

Example 3:

Input: [[1,4],[2,3]] Output: [[1,4]]

Jnaneshwara Reddy Satti

Builder · ClearCode

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Algorithm Visualizer

O(N log N)

Before starting this video, please check the description to ensure you know the prerequisites. If you're comfortable with arrays and hash maps, let's go!

TEST CASE: []O(N)

clearcode.in

Execution Trace

1def merge(intervals):

2 if not intervals:

3 return []

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

5 merged = [intervals[0]]

6 for current in intervals[1:]:

7 last_merged = merged[-1]

8 if current[0] <= last_merged[1]:

9 last_merged[1] = max(last_merged[1], current[1])

10 else:

11 merged.append(current)

12 return merged

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