Class Alldiff

  • All Implemented Interfaces:
    SatisfiedPresent, UsesQueueVariable
    Direct Known Subclasses:
    Circuit, Subcircuit

    public class Alldiff
    extends Alldifferent
    Alldiff constraint assures that all FDVs has different values. It uses bounds consistency technique as described in the paper by Alejandro Lopez-Ortiz, Claude-Guy Quimper, John Tromp, Peter van Beek, "A fast and simple algorithm for bounds consistency of the alldifferent constraint", Proceedings of the 18th international joint conference on Artificial intelligence (IJCAI'03), Pages 245-250. Before using bounds consistency it calls consistency method for ground variables.

    It extends basic functionality of Alldifferent constraint.

    Version:
    4.7
    • Field Detail

      • idNumber

        static java.util.concurrent.atomic.AtomicInteger idNumber
      • t

        private int[] t
      • d

        private int[] d
      • h

        private int[] h
      • bounds

        private int[] bounds
      • nb

        private int nb
    • Constructor Detail

      • Alldiff

        protected Alldiff()
      • Alldiff

        public Alldiff​(IntVar[] variables)
        It constructs the alldiff constraint for the supplied variable.
        Parameters:
        variables - variables which are constrained to take different values.
      • Alldiff

        public Alldiff​(java.util.List<? extends IntVar> variables)
        It constructs the alldiff constraint for the supplied variable.
        Parameters:
        variables - variables which are constrained to take different values.
    • Method Detail

      • impose

        public void impose​(Store store)
        Description copied from class: Constraint
        It imposes the constraint in a given store.
        Overrides:
        impose in class Alldifferent
        Parameters:
        store - the constraint store to which the constraint is imposed to.
      • consistency

        public void consistency​(Store store)
        Description copied from class: Constraint
        It is a (most probably incomplete) consistency function which removes the values from variables domains. Only values which do not have any support in a solution space are removed.
        Overrides:
        consistency in class Alldifferent
        Parameters:
        store - constraint store within which the constraint consistency is being checked.
      • init

        private void init()
      • updateLB

        private void updateLB()
      • updateUB

        private void updateUB()
      • pathset

        private void pathset​(int[] v,
                             int start,
                             int end,
                             int to)
      • pathmin

        private int pathmin​(int[] v,
                            int i)
      • pathmax

        private int pathmax​(int[] v,
                            int i)
      • toString

        public java.lang.String toString()
        Description copied from class: Constraint
        It produces a string representation of a constraint state.
        Overrides:
        toString in class Alldifferent
      • queueVariable

        public void queueVariable​(int level,
                                  Var var)
        Description copied from class: Constraint
        This is a function called to indicate which variable in a scope of constraint has changed. It also indicates a store level at which the change has occurred.
        Overrides:
        queueVariable in class Alldifferent
        Parameters:
        level - the level of the store at which the change has occurred.
        var - variable which has changed.