public class Alldistinct extends Constraint implements UsesQueueVariable, Stateful, SatisfiedPresent
This implementation is based on Regin paper. It uses slightly modified HopcroftKarp algorithm to compute maximum matching. The value graph is analysed and Tarjan algorithm for finding strongly connected components is used. Maximum matching and Value Graph is stored as TimeStamp Mutable variables to minimize recomputation. Value graph is expensive in terms of memory usage. Use this constraint with care. One variable with domain 0..1000000 will make it use few MB already and kill the efficiency.
Modifier and Type  Field and Description 

int 
consistencyChecks
It counts the number of executions of the consistency function.

int 
fullConsistencyPassesWithNarrowingEvent
It computes how many times did consistency execution has been
reexecuted due to narrowing event at the end of the consistency
function.

IntVar[] 
list
It specifies all variables which have to have different values.

atomicExecution, consistencyPruningEvents, constraintScope, earlyTerminationOK, increaseWeight, numberId, scope, trace
queueIndex
Constructor and Description 

Alldistinct(IntVar[] list)
It constructs an alldistinct constraint.

Alldistinct(List<? extends IntVar> list)
It constructs an alldistinct constraint.

Modifier and Type  Method and Description 

void 
consistency(Store store)
It is a (most probably incomplete) consistency function which removes the
values from variables domains.

int 
getDefaultConsistencyPruningEvent() 
Constraint 
getGuideConstraint()
It specifies a constraint which if imposed by search will enhance
propagation of this constraint.

int 
getGuideValue()
This function provides a value which if assigned to a variable returned
by getGuideVariable() will enhance propagation of this constraint.

Var 
getGuideVariable()
This function provides a variable which assigned a value returned
by will enhance propagation of this constraint.

void 
impose(Store store)
It imposes the constraint in a given store.

void 
queueVariable(int level,
Var var)
This is a function called to indicate which variable in a scope of
constraint has changed.

void 
removeLevel(int level)
This function is called in case of the backtrack, so a constraint can
clear the queue of changed variables which is no longer valid.

boolean 
satisfied()
It checks if the constraint is satisfied.

String 
toString()
It produces a string representation of a constraint state.

afc, arguments, cleanAfterFailure, decompose, getConsistencyPruningEvent, grounded, grounded, id, impose, imposeDecomposition, increaseWeight, intArrayToString, long2int, numberArgs, removeConstraint, requiresMonotonicity, setConsistencyPruningEvent, setConstraintScope, setScope, setScope, setScope, setScope, setScope, setWatchedVariableGrounded, supplyGuideFeedback, updateAFC, watchedVariableGrounded
auxiliaryVariables, checkInput, checkInput, checkInputForDuplication, checkInputForDuplicationSkipSingletons, checkInputForNullness, checkInputForNullness, checkInputForNullness, derivative, getDubletonsSkipSingletons, imposeDecomposition
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
isStateful
public int consistencyChecks
public int fullConsistencyPassesWithNarrowingEvent
public IntVar[] list
public Alldistinct(IntVar[] list)
list
 an array of variables.public void removeLevel(int level)
Stateful
removeLevel
in interface Stateful
level
 the level which is being removed.public void consistency(Store store)
Constraint
consistency
in class Constraint
store
 constraint store within which the constraint consistency is being checked.public int getDefaultConsistencyPruningEvent()
getDefaultConsistencyPruningEvent
in class Constraint
public void impose(Store store)
Constraint
impose
in class Constraint
store
 the constraint store to which the constraint is imposed to.public void queueVariable(int level, Var var)
Constraint
queueVariable
in class Constraint
level
 the level of the store at which the change has occurred.var
 variable which has changed.public boolean satisfied()
SatisfiedPresent
Implementations of this interface for constraints that are not PrimitiveConstraint may require constraint imposition and consistency check as a requirement to work correctly.
satisfied
in interface SatisfiedPresent
public String toString()
Constraint
toString
in class Constraint
public Constraint getGuideConstraint()
Constraint
getGuideConstraint
in class Constraint
public int getGuideValue()
Constraint
getGuideValue
in class Constraint
public Var getGuideVariable()
Constraint
getGuideVariable
in class Constraint
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