Class SetVarBranch

gecode/set.hh:1309–1364

* \brief Which variable to select for branching * * \ingroup TaskModelSetBranch */

   * \ingroup TaskModelSetBranch
   */
  class SetVarBranch : public VarBranch<SetVar> {
  public:
    /// Which variable selection
    enum Select {
      SEL_NONE = 0,        ///< First unassigned
      SEL_RND,             ///< Random (uniform, for tie breaking)
      SEL_MERIT_MIN,       ///< With least merit
      SEL_MERIT_MAX,       ///< With highest merit
      SEL_DEGREE_MIN,      ///< With smallest degree
      SEL_DEGREE_MAX,      ///< With largest degree
      SEL_AFC_MIN,         ///< With smallest accumulated failure count
      SEL_AFC_MAX,         ///< With largest accumulated failure count
      SEL_ACTION_MIN,      ///< With lowest action
      SEL_ACTION_MAX,      ///< With highest action
      SEL_CHB_MIN,         ///< With lowest CHB Q-score
      SEL_CHB_MAX,         ///< With highest CHB Q-score
      SEL_MIN_MIN,         ///< With smallest minimum unknown element
      SEL_MIN_MAX,         ///< With largest minimum unknown element
      SEL_MAX_MIN,         ///< With smallest maximum unknown element
      SEL_MAX_MAX,         ///< With largest maximum unknown element
      SEL_SIZE_MIN,        ///< With smallest unknown set
      SEL_SIZE_MAX,        ///< With largest unknown set
      SEL_DEGREE_SIZE_MIN, ///< With smallest degree divided by domain size
      SEL_DEGREE_SIZE_MAX, ///< With largest degree divided by domain size
      SEL_AFC_SIZE_MIN,    ///< With smallest accumulated failure count divided by domain size
      SEL_AFC_SIZE_MAX,    ///< With largest accumulated failure count divided by domain size
      SEL_ACTION_SIZE_MIN, ///< With smallest action divided by domain size
      SEL_ACTION_SIZE_MAX, ///< With largest action divided by domain size
      SEL_CHB_SIZE_MIN,    ///< With smallest CHB Q-score divided by domain size
      SEL_CHB_SIZE_MAX     ///< With largest CHB Q-score divided by domain size
    };
  protected:
    /// Which variable to select
    Select s;
  public:
    /// Initialize with strategy SEL_NONE
    SetVarBranch(void);
    /// Initialize with random number generator \a r
    SetVarBranch(Rnd r);
    /// Initialize with selection strategy \a s and tie-break limit function \a t
    SetVarBranch(Select s, BranchTbl t);
    /// Initialize with selection strategy \a s, decay factor \a d, and tie-break limit function \a t
    SetVarBranch(Select s, double d, BranchTbl t);
    /// Initialize with selection strategy \a s, afc \a a, and tie-break limit function \a t
    SetVarBranch(Select s, SetAFC a, BranchTbl t);
    /// Initialize with selection strategy \a s, action \a a, and tie-break limit function \a t
    SetVarBranch(Select s, SetAction a, BranchTbl t);
    /// Initialize with selection strategy \a s, CHB \a c, and tie-break limit function \a t
    SetVarBranch(Select s, SetCHB c, BranchTbl t);
    /// Initialize with selection strategy \a s, branch merit function \a mf, and tie-break limit function \a t
    SetVarBranch(Select s, SetBranchMerit mf, BranchTbl t);
    /// Return selection strategy
    Select select(void) const;
    /// Expand AFC, action, and CHB
    void expand(Home home, const SetVarArgs& x);
  };

  /**