// bubble sort method for service name
  private static void sortByService() {
    for(int a = 0; a < highSubscript; ++a) {
      for(int b = 0; b < highSubscript; ++b) {
        if(services[b].getService().compareTo(services[b + 1].getService()) > 0) {
          Service temp = services[b];
          services[b] = services[b + 1];
          services[b + 1] = temp;
        }
      }
    }
  }

  // bubble sort method for price
  private static void sortByPrice() {
    for(int a = 0; a < highSubscript; ++a) {
      for(int b = 0; b < highSubscript; ++b) {
        if(services[b].getPrice() > services[b + 1].getPrice()) {
          Service temp = services[b];
          services[b] = services[b + 1];
          services[b + 1] = temp;
        }
      }
    }
  }

  //buble sort method for time
  private static void sortByTime() {
    for(int a = 0; a < highSubscript; ++a) {
      for(int b = 0; b < highSubscript; ++b) {
        if(services[b].getTime() > services[b + 1].getTime()) {
          Service temp = services[b];
          services[b] = services[b + 1];
          services[b + 1] = temp;
        }
      }
    }
  }