private double testDoublyLinkedListDeletions(int inserts) {
        System.out.println("Testing DoublyLinkedList with " + inserts + " deletions");

        long[] times = new long[20];
        long startTime;
        long endTime;

        for (int i = 0; i < 20; i++) {
            doublyLinkedList = new DoublyLinkedList();
            for (int j = 0; j < inserts; j++) {
                doublyLinkedList.insert(null);
            }
            startTime = System.currentTimeMillis();
            for (int j = 0; j < inserts; j++) {
                doublyLinkedList.delete();
            }
            endTime = System.currentTimeMillis();
            times[i] = endTime - startTime;
        }

        double returnValue = 0;
        for (int i = 0; i < times.length; i++) {
            returnValue += times[i];
        }
        return returnValue / 20.0;
    }