Intervals are represented by a pair of integers in the form of an array. The first value of the interval will always be less than the second value. Interval example: [1, 5] is an interval from 1 to 5.

You are given a 2D integer array intervals, where intervals[i] = [lefti, righti] describes the ith interval starting from lefti and ending at righti (inclusive). The size of the array is n and ...