public static SetNode Unite(SetNode A, SetNode B)
{
if (A.Type == SetNode.NodeType.OPERATOR || B.Type == SetNode.NodeType.OPERATOR)
{
return(A & B);
}
var newSet = new Set();
foreach (var piece in A as Set)
{
newSet.AddPiece(piece);
}
foreach (var piece in B as Set)
{
newSet.AddPiece(piece);
}
return(newSet);
}