private static int CountLostValues(CSP <Var, Val> csp, Assignment <Var, Val> assignment, Var var, Val value)
{
var result = 0;
var assign = new Assignment <Var, Val>();
assign.Add(var, value);
foreach (var constraint in csp.GetConstraints(var))
{
if (constraint.GetScope().Count() == 2)
{
Var neighbor = csp.GetNeighbor(var, constraint);
if (!assignment.Contains(neighbor))
{
foreach (var val in csp.GetDomain(neighbor))
{
assign.Add(neighbor, val);
if (!constraint.IsSatisfiedWith(assign))
{
++result;
}
}
}
}
}
return(result);
}
public IEnumerable <Val> Apply(CSP <Var, Val> csp, Assignment <Var, Val> assignment, Var var)
{
var pairs = new List <KeyValuePair <Val, int> >();
foreach (Val value in csp.GetDomain(var))
{
var num = CountLostValues(csp, assignment, var, value);
pairs.Add(new KeyValuePair <Val, int>(value, num));
}
return(pairs.OrderBy(p => p.Value).Select(p => p.Key));
}
public virtual IEnumerable <Var> Apply(CSP <Var, Val> csp, IEnumerable <Var> vars)
{
var result = new List <Var>();
var minValues = int.MaxValue;
foreach (var var in vars)
{
var values = csp.GetDomain(var).Count();
if (values < minValues)
{
result.Clear();
minValues = values;
}
if (values == minValues)
{
result.Add(var);
}
}
return(result);
}
private IEnumerable <Val> OrderDomainValues(CSP <Var, Val> csp, Assignment <Var, Val> assignment, Var var)
{
return((ValueOrderingStrategy != null)
? ValueOrderingStrategy.Apply(csp, assignment, var)
: csp.GetDomain(var));
}
