code: package org.optsol.project_scheduling.mrcpsp.constants.sub;
  
  import java.util.List;
  import java.util.stream.Collectors;
  import java.util.stream.IntStream;
  
  public interface IConstants_V extends IConstants_A {
  
    //index of dummy activity representing project start
    default int get_dummy_activity_project_start() {
      return 0;
    }
  
    //index of dummy activity representing project start
    default int get_A_bar() {
      return get_card_A() + 1;
    }
  
    // dummy source and sink node
    default List<Integer> get_dummies() {
      return List.of(get_dummy_activity_project_start(), get_A_bar());
    }
  
    // set of activities (incl. dummy start 0 and terminal activity \bar{A})
    default List<Integer> get_V() {
      return IntStream.rangeClosed(get_dummy_activity_project_start(), get_A_bar()).boxed()
          .collect(Collectors.toList());
    }
  }
  