/// <summary>
/// Return strongly connected components
/// Does not include Event variable
/// this.transitionsNoEvents is the transtion from reachble states
/// From Feasible algorithm in the article "LTL Symbolic MC"
/// [ REFS: 'result', DEREFS:]
/// </summary>
/// <param name="model"></param>
/// <param name="initState"></param>
/// <param name="finalState"></param>
/// <returns></returns>
private CUDDNode SCCHull(Model model, CUDDNode initState, CUDDNode finalState)
{
CUDDNode old = CUDD.Constant(0);
CUDD.Ref(initState);
CUDDNode New = model.SuccessorsStart(initState, this.transitionsNoEvents);
//Limit transition to transition of reachable states
CUDD.Ref(New);
transitionsNoEvents = CUDD.Function.And(transitionsNoEvents, New);
//Pruning step: remove states whose succeessors are not belong to that set
while (!New.Equals(old))
{
CUDD.Deref(old);
CUDD.Ref(New);
old = New;
//final state as justice requirement
//new = (new and J) x R*
CUDD.Ref(finalState);
New = model.SuccessorsStart(CUDD.Function.And(New, finalState), this.transitionsNoEvents);
//while new is not comprised of the set of all successors of new states
while (true)
{
CUDD.Ref(New, New);
CUDDNode temp = CUDD.Function.And(New, model.Successors(New, this.transitionsNoEvents));
if (temp.Equals(New))
{
CUDD.Deref(temp);
break;
}
else
{
CUDD.Deref(New);
New = temp;
}
}
}
return New;
}
