BDDNode MakeNode(int varId, BDDNode low, BDDNode high)
{
if (low == high)
{
return(low);
}
return(GetNode(varId, low.GetId(), high.GetId())); //найти в таблице с нодами;
}
private BDDNode Contraction(int v, BDDNode x, bool pos) // сужение функции
{
if (v != x.GetVarId())
{
return(x);
}
return((pos) ? x.GetHigh() : x.GetLow());
}
private BDDNode ConstructOneVarTree(int n, int id)
{
BDDNode root = new BDDNode(n, id);
root.SetLow(zero);
root.SetHigh(one);
return(root);
}
public BDDNode CreateVars(int n)//переделать для robdd
{
if (nodeTable.ContainsKey(Tuple.Create(n, zero.GetId(), one.GetId())))
{
return(nodeTable[Tuple.Create(n, zero.GetId(), one.GetId())]);
}
BDDNode newNode = ConstructOneVarTree(n, id++);
InsertNode(newNode);
return(newNode);
}
void InsertNode(BDDNode node) // Добавление в таблицу
{
int leftId = (node.GetLow() == null) ? 0 : node.GetLow().GetId();
int rightId = (node.GetHigh() == null) ? 0 : node.GetHigh().GetId();
int varId = node.GetVarId();
if (!nodeTable.ContainsKey(Tuple.Create(varId, leftId, rightId)))
{
nodeTable.Add(Tuple.Create(varId, leftId, rightId), node);
}
}
public BDD(int[] vals)
{
vars = vals;
nodeTable = new Dictionary <Tuple <int, int, int>, BDDNode>();
id = 2;
// construct leaf nodes 0 and 1 and save to map
zero = new BDDNode(-2, 0, true);
one = new BDDNode(-1, 1, true);
// InsertNode(zero);
// InsertNode(one);
}
private int TopVar(BDDNode f, BDDNode g, BDDNode h)
{
if (g.IsTerminal)
{
if (h.IsTerminal)
{
return(f.GetVarId());
}
return(vars[Math.Min(
Array.IndexOf(vars, f.GetVarId()), Array.IndexOf(vars, h.GetVarId()))]);
}
if (h.IsTerminal)
{
return(vars[Math.Min(Array.IndexOf(vars, f.GetVarId()), Array.IndexOf(vars, g.GetVarId()))]);
}
return(vars[Math.Min(
Math.Min(Array.IndexOf(vars, f.GetVarId()), Array.IndexOf(vars, g.GetVarId())),
Array.IndexOf(vars, h.GetVarId()))]);
}
private BDDNode ITE(BDDNode f, BDDNode g, BDDNode h)
{
//Один из следующих терминальных
//ite(F; 1; 0) = ite(1; F; G) = ite(0; G; F ) = ite(G; F; F ) = F;
if (g.GetId() == one.GetId() && h.GetId() == zero.GetId())
{
return(f);
}
if (f.GetId() == one.GetId())
{
return(g); //one
}
if (f.GetId() == zero.GetId())
{
return(h); //zero
}
if (g.GetVarId() == h.GetVarId())
{
return(g);
}
//Normalize
//ite(F; F; G) =) ite(F; 1; G)
//ite(F; G; F ) =) ite(F; G; 0)
if (BDDNode.Eq(f, g))
{
h = g;
g = one;
}
if (BDDNode.Eq(f, h))
{
h = zero;
}
//где-то здесь ошибка
if (cache.ContainsKey(Tuple.Create(f.GetId(), h.GetId(), g.GetId())))// HASH_LOOKUP_COMPUTED_TABLE
{
return(cache[Tuple.Create(f.GetId(), h.GetId(), g.GetId())]);
}
int v = TopVar(f, g, h); // top variable from f,g,h
// recursive calls
BDDNode fn = ITE(Contraction(v, f, true), //сужение по high
Contraction(v, g, true),
Contraction(v, h, true));
BDDNode gn = ITE(Contraction(v, f, false),//сужение по low
Contraction(v, g, false),
Contraction(v, h, false));
if (BDDNode.Eq(fn, gn))
{
return(gn);
}
BDDNode node = MakeNode(v, gn, fn);// HASH_LOOKUP_UNIQUE_TABLE
if (node == null)
{
node = new BDDNode(v, id++, gn, fn);
InsertNode(node); // insert into UNIQUE_TABLE
}
if (!cache.ContainsKey(Tuple.Create(v, gn.GetId(), fn.GetId())))
{
cache.Add(Tuple.Create(v, gn.GetId(), fn.GetId()), node);//INSERT_COMPUTED_TABLE
}
return(node);
}
public BDDNode NOT(BDDNode f)
{
var ite = ITE(f, zero, one);
return(ite);
}
public BDDNode OR(BDDNode f, BDDNode g)
{
var ite = ITE(f, one, g);
return(ite);
}
public BDDNode AND(BDDNode f, BDDNode g)
{
var ite = ITE(f, g, zero);
return(ite);
}