// Extract a plan for resatisfaction starting from the outputs of
// the given constraints, usually a set of input constraints.
//
public Plan extractPlanFromConstraints(ArrayList constraints)
{
ArrayList sources = new ArrayList();
for (int i = 0; i < constraints.Count; ++i)
{
Constraint c = (Constraint)constraints[i];
if (c.isInput() && c.isSatisfied())
{
sources.Add(c);
}
}
return(makePlan(sources));
}
public void addConstraintsConsumingTo(Variable v, ArrayList coll)
{
Constraint determiningC = v.determinedBy;
ArrayList cc = v.constraints;
for (int i = 0; i < cc.Count; ++i)
{
Constraint c = (Constraint)cc[i];
if (c != determiningC && c.isSatisfied())
{
coll.Add(c);
}
}
}
// Update the walkabout strengths and stay flags of all variables
// downstream of the given constraint. Answer a collection of
// unsatisfied constraints sorted in order of decreasing strength.
//
public ArrayList removePropagateFrom(Variable outvar)
{
outvar.determinedBy = null;
outvar.walkStrength = Strength.weakest;
outvar.stay = true;
ArrayList unsatisfied = new ArrayList();
ArrayList todo = new ArrayList();
todo.Add(outvar);
while (!(todo.Count == 0))
{
#if USE_STACK
Variable v = (Variable)todo[todo.Count - 1];
todo.RemoveAt(todo.Count - 1);
#else
Variable v = (Variable)todo[0];
todo.RemoveAt(0);
#endif
for (int i = 0; i < v.constraints.Count; ++i)
{
Constraint c = (Constraint)v.constraints[i];
if (!c.isSatisfied())
{
unsatisfied.Add(c);
}
}
Constraint determiningC = v.determinedBy;
for (int i = 0; i < v.constraints.Count; ++i)
{
Constraint nextC = (Constraint)v.constraints[i];
if (nextC != determiningC && nextC.isSatisfied())
{
nextC.recalculate();
todo.Add(nextC.output());
}
}
}
return(unsatisfied);
}