Merge Intervalsmedium

import java.util.*;

public class Main {
    public static int[][] merge(int[][] intervals) {
        // TODO: sort by start, then merge overlapping intervals
        return new int[][]{};
    }

    public static void main(String[] args) {
        int[][] a = {{1,3},{2,6},{8,10},{15,18}};
        System.out.println(Arrays.deepToString(merge(a)));
    }
}