DIY: Find Interval Sets

Problem statement

You are given an array of intervals, and you have to organize them into sets such that only one interval can occupy a set at a time. Your job is to find the minimum number of sets we need to process all the intervals.

Input

The input is an array of arrays. The nested arrays contain two integers representing the starting and ending points of the interval. The following is an example of input:

[[1, 4], [2, 5], [4, 8], [5, 6], [5, 8], [6, 7]]

Output

The output is an integer representing the number of sets needed to process the intervals. The following is an example output:

3

Coding exercise

You need to implement the function findSets(intervals), where intervals is the array of intervals. The function returns an integer representing the number of sets that are needed.