Description

Given an array of intervals where intervals[i] = [start, end], merge all overlapping intervals and return an array of the non-overlapping intervals that cover all the intervals in the input.

Input format / Clarification:

• Line 1: JSON array of intervals

Examples

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

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

Input:
[[1,4],[0,4]]
Output:
[[0,4]]

Note:

Your program must print the merged intervals as a JSON array.