private void ConvertNFAToDFA()
{
var nfaStates = m_nfa.States;
//state 0 is an empty state. All invalid inputs go to state 0
DFAState state0 = new DFAState();
AddDFAState(state0);
//state 1 is closure(nfaState[0])
DFAState preState1 = new DFAState();
int nfaStartIndex = m_nfa.EntryEdge.TargetState.Index;
Debug.Assert(nfaStartIndex >= 0);
preState1.NFAStateSet.Add(nfaStartIndex);
DFAState state1 = GetClosure(preState1);
AddDFAState(state1);
//begin algorithm
int p = 1, j = 0;
var newStates = new DFAState[CompactCharSetManager.MaxClassIndex + 1];
while (j <= p)
{
var sourceState = m_dfaStates[j];
Parallel.For(CompactCharSetManager.MinClassIndex, CompactCharSetManager.MaxClassIndex + 1,
symbol =>
{
DFAState e = GetDFAState(sourceState, symbol);
newStates[symbol] = e;
}
);
for (int symbol = CompactCharSetManager.MinClassIndex; symbol <= CompactCharSetManager.MaxClassIndex; symbol++)
{
DFAState e = newStates[symbol];
bool isSetExist = false;
for (int i = 0; i <= p; i++)
{
if (e.NFAStateSet.SetEquals(m_dfaStates[i].NFAStateSet))
{
//an existing dfa state
DFAEdge newEdge = new DFAEdge(symbol, m_dfaStates[i]);
sourceState.AddEdge(newEdge);
isSetExist = true;
}
}
if (!isSetExist)
{
//a new set of nfa states (a new dfa state)
p += 1;
AddDFAState(e);
DFAEdge newEdge = new DFAEdge(symbol, e);
sourceState.AddEdge(newEdge);
}
}
j += 1;
}
}
internal void AddEdge(DFAEdge edge)
{
CodeContract.RequiresArgumentNotNull(edge, "edge");
m_outEdges.Add(edge);
}