class TPSMutator {

    public long serverDownTime() {
        long lastDate = -1;
        long downTime = 0;
        tpsData.sort(new TPSComparator());
        for (TPS tps : tpsData) {
            long date = tps.getDate();
            if (lastDate == -1) {
                lastDate = date;
                continue;
            }

            long diff = date - lastDate;
            if (diff > TimeUnit.MINUTES.toMillis(3L)) {
                downTime += diff;
            }
            lastDate = date;
        }

        return downTime;
    }

    public  TPSMutator(List<TPS> tpsData);

}