#106 Custom List Sorting by the Prefix of Another List

There are two lists, m1 and m2. Sort m2 so that the elements from m1 appear at the beginning, followed by all remaining elements sorted in natural order:

public class Main
{
    public static void main(String[] args) {
        List<Integer> m1 = Arrays.asList(5, 3, 0);
        List<Integer> m2 = new ArrayList<>(Arrays.asList(7, 3, 5, 2, 9, 8, 4, 1, 6));

        List<Integer> result = customSort(m1, m2);

        System.out.println(result); // [5, 3, 1, 2, 4, 6, 7, 8, 9]
    }

    public static List<Integer> customSort(List<Integer> m1, List<Integer> m2) {
        ...
    }
}