private GeneratorNode generateNode()
{
HashSet<GeneratorNode> spawnedNodes;
HashSet<GeneratorNode> newNodes = new HashSet<GeneratorNode>();
int size = 0, atoms = 0;
long timeBegin = Stopwatch.GetTimestamp();
// Takes each node and applies its decomposition
foreach (GeneratorNode wn in m_nodes)
{
GeneratorNode wn2 = new GeneratorNode();
wn2.setGamma(wn.getDelta());
spawnedNodes = wn2.spawn();
foreach (GeneratorNode gn in spawnedNodes)
{
newNodes.Add(gn);
}
// Shortcut: as soon as one branch returns something, we skip the others
if (spawnedNodes.Count > 0)
{
break;
}
}
long timeEnd = Stopwatch.GetTimestamp();
System.Console.WriteLine("Finished producing the " + newNodes.Count + "nodes " + (timeEnd - timeBegin));
timeBegin = Stopwatch.GetTimestamp();
// Remember the new nodes
m_nodes = newNodes;
// Updates statistics about maximum number of nodes
size = m_nodes.Count;
if (size > m_maxNodes)
{
m_maxNodes = size;
}
// Updates statistics about total number of formulae
size = 0;
atoms = 0;
foreach (GeneratorNode wn in m_nodes)
{
size += wn.getSize();
atoms += wn.getAtoms();
}
if (size > m_maxFormulae)
{
m_maxFormulae = size;
}
if (atoms > m_maxAtoms)
{
m_maxAtoms = atoms;
}
// We remove nodes that don't contain any OPlus
// (i.e., that don't tell us to do anything)
// and check at the same time if at least one node is sound
bool hasSound = false;
foreach (GeneratorNode wn in m_nodes)
{
HashSet<OPlus> opluses = wn.getOPluses();
bool contains_element = false;
foreach (OPlus op in opluses)
{
// Remove conditions that only assert path existence
if (!op.getOperand().Equals(Operator.m_falseAtom) &&
!op.getOperand().Equals(Operator.m_trueAtom))
{
contains_element = true;
}
}
if (!contains_element)
{
m_nodes.Remove(wn);
}
else
{
if (wn.Sound)
{
hasSound = true;
}
}
}
// Can we produce a new message?
if (m_nodes.Count == 0)
{
// No!
return null;
}
// We remove all nodes whose OPluses are contradictory
/*it = m_nodes.iterator();
while (it.hasNext())
{
GeneratorNode wn = it.next();
if (wn.containsOPlusContradiction())
it.remove();
}*/
// Is there at least one remaining sound node?
if (hasSound)
{
// Yes: then let's remove any unsound node
foreach (GeneratorNode wn in m_nodes)
{
if (!wn.Sound)
{
m_nodes.Remove(wn);
}
}
}
timeEnd = Stopwatch.GetTimestamp();
System.Console.WriteLine("Finished pruning " + (timeEnd - timeBegin));
// Pick *one* of the nodes randomly
long pickIndex = (long)System.Math.Round(new System.Random().NextDouble() * (double)(m_nodes.Count - 1));
int i = 0;
GeneratorNode pickedNode = null;
foreach (GeneratorNode gn in m_nodes)
{
if (i == pickIndex)
{
pickedNode = gn;
break;
}
i++;
}
// Keep only the selected node for the next state
m_nodes = new HashSet<GeneratorNode>();
m_nodes.Add(pickedNode);
// Return the picked node
return pickedNode;
}
