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# Remove Covered Intervals

Given a list of intervals, remove all intervals that are covered by another interval in the list. Interval `[a,b)` is covered by interval `[c,d)` if and only if `c <= a` and `b <= d`.

After doing so, return the number of remaining intervals.

**Example 1:**

```
Input: intervals = [[1,4],[3,6],[2,8]]
Output: 2
Explanation: Interval [3,6] is covered by [2,8], therefore it is removed.
```

**Constraints:**

* `1 <= intervals.length <= 1000`
* `0 <= intervals[i][0] < intervals[i][1] <= 10^5`
* `intervals[i] != intervals[j]` for all `i != j`

```java
class Solution {
    public int removeCoveredIntervals(int[][] intervals) {
        Arrays.sort(intervals, (a, b) -> a[0] == b[0] ? b[1] - a[1] : a[0] - b[0]);
        int count = 0;
        int currentEnd = 0;
        // By sorting we make sure that interval before will definately will have
        // smaller start time therefore we only need to take care of end time
        for (int[] interval : intervals) {
            if (currentEnd < interval[1]) {
                count++;
                currentEnd = interval[1];
            }
        }
        return count;
    }
}
```