internal static Set IntersectFiniteSetAndSet(FiniteSet finite, Set set)
{
if (set is FiniteSet another)
{
return(FiniteSet.Intersect(finite, another));
}
var fsb = new FiniteSetBuilder();
var amb = new FiniteSetBuilder();
foreach (var elem in finite)
{
if (!set.TryContains(elem, out var contains))
{
amb.Add(elem);
}
else if (contains)
{
fsb.Add(elem);
}
}
return(amb.IsEmpty ? fsb.ToFiniteSet() : amb.ToFiniteSet().Unite(fsb.ToFiniteSet()));
}
internal static Set SetSubtractSetAndFiniteSet(Set set, FiniteSet finite)
{
if (set is FiniteSet another)
{
return(FiniteSet.Subtract(another, finite));
}
var fsb = new FiniteSetBuilder(finite);
foreach (var el in finite)
{
if (set.TryContains(el, out var contains) && !contains)
{
fsb.Remove(el);
}
}
return(fsb.IsEmpty ? set : set.SetSubtract(fsb.ToFiniteSet()));
}