The idea is that for the result distinct Interval, the latter one's start must > previous one's end.

```
public List<Interval> merge(List<Interval> intervals) {
// sort start&end
int n = intervals.size();
int[] starts = new int[n];
int[] ends = new int[n];
for (int i = 0; i < n; i++) {
starts[i] = intervals.get(i).start;
ends[i] = intervals.get(i).end;
}
Arrays.sort(starts);
Arrays.sort(ends);
// loop through
List<Interval> res = new ArrayList<Interval>();
for (int i = 0, j = 0; i < n; i++) { // j is start of interval.
if (i == n - 1 || starts[i + 1] > ends[i]) {
res.add(new Interval(starts[j], ends[i]));
j = i + 1;
}
}
return res;
}
```