# Interval Duration

You are given a two-dimensional list of integers `intervals`

where each list represents an inclusive `[start, end]`

interval.

Return the total unique duration it covers.

**Constraints**

`n ≤ 100,000`

where`n`

is length of`intervals`

.

https://binarysearch.com/problems/Interval-Duration

## Examples

### Example 1

**Input**

- intervals =

```
[[45,60],
[ 1, 5],
[ 5,15],
[ 2, 3]]
```

**Output**

- answer =
`31`

**Explanation**

The total unique covered distance is `[45, 60]`

(duration of `16`

) and `[1 ,15]`

(duration of `15`

).

## Leave a comment