public void printMobileStatistics(LinkedList<Call> calls){
        HashMap<String, Integer> stats = new HashMap<String, Integer>();
        for (Call call:calls){
            String operator = MobileCodes.get(call.getCall()[2].substring(0,2));
            if (stats.containsKey(operator)){
                stats.put(operator, Integer.valueOf(MobileCodes.get(operator)) + Integer.valueOf(call.getCall()[4]));
            }
            else stats.put(operator, Integer.valueOf(call.getCall()[4]));
        }
    }