/// <summary>Create the transitions</summary>
private void CreateTransitions()
{
int cont = 0;
List <int> initialStateValue = FirstLastTable.FirstOrDefault(x => x.Key.Item1 == Tree.Identifier).Value
.Item1[0];
Tuple <string, List <int> > initialState = new Tuple <string, List <int> >("State 0", initialStateValue);
Queue <Tuple <string, List <int> > > pendingStates = new Queue <Tuple <string, List <int> > >();
pendingStates.Enqueue(initialState);
while (pendingStates.Count > 0)
{
Dictionary <string, List <int> > values = new Dictionary <string, List <int> >();
Tuple <string, List <int> > state = pendingStates.Peek();
foreach (int number in state.Item2)
{
Tuple <int, string> followKey = FollowsTable.FirstOrDefault(x => x.Key.Item1 == number).Key;
string transitionWith = followKey.Item2;
List <int> transitionValues = new List <int>(FollowsTable[followKey]);
if (transitionValues.Count > 0)
{
if (values.ContainsKey(transitionWith))
{
foreach (int element in transitionValues)
{
if (!values[transitionWith].Contains(element))
{
values[transitionWith].Add(element);
}
}
}
else
{
values.Add(transitionWith, transitionValues);
}
values[transitionWith].Sort();
}
}
foreach (KeyValuePair <string, List <int> > value in values)
{
if (!Transitions.Any(x => x.Key.Item2.SequenceEqual(value.Value)) &&
!pendingStates.Any(x => x.Item2.SequenceEqual(value.Value)))
{
cont++;
Tuple <string, List <int> > newState = new Tuple <string, List <int> >("State " + cont, value.Value);
pendingStates.Enqueue(newState);
}
}
Tuple <string, List <int>, bool> key;
if (state.Item2.Contains(Tree.RightChild.Identifier))
{
key = new Tuple <string, List <int>, bool>(state.Item1, state.Item2, true);
}
else
{
key = new Tuple <string, List <int>, bool>(state.Item1, state.Item2, false);
}
pendingStates.Dequeue();
Transitions.Add(key, values);
}
}
/// <summary>Transverse the tree and create the first and lasts</summary>
/// <param name="node">The current node</param>
private void CreateFirstlastsTable(Node node)
{
if (node != null)
{
CreateFirstlastsTable(node.LeftChild);
CreateFirstlastsTable(node.RightChild);
if (node.LeftChild == null && node.RightChild == null)
{
List <int> firsts = new List <int> {
node.Identifier
};
List <int> lasts = new List <int> {
node.Identifier
};
List <int>[] values = new List <int>[2] {
firsts, lasts
};
Tuple <int, string> identifier = new Tuple <int, string>(node.Identifier, node.Value);
Tuple <List <int>[], bool> data = new Tuple <List <int>[], bool>(values, false);
FirstLastTable.Add(identifier, data);
}
else
{
List <int> firsts = new List <int>();
List <int> lasts = new List <int>();
bool nullable = false;
Tuple <int, string> key = new Tuple <int, string>(node.LeftChild.Identifier, node.LeftChild.Value);
Tuple <List <int>[], bool> c1 = FirstLastTable[key];
if (node.Value.Equals("|"))
{
key = new Tuple <int, string>(node.RightChild.Identifier, node.RightChild.Value);
Tuple <List <int>[], bool> c2 = FirstLastTable[key];
firsts.AddRange(c1.Item1[0]);
firsts.AddRange(c2.Item1[0]);
lasts.AddRange(c1.Item1[1]);
lasts.AddRange(c2.Item1[1]);
if (c1.Item2 || c2.Item2)
{
nullable = true;
}
}
else if (node.Value.Equals("·"))
{
key = new Tuple <int, string>(node.RightChild.Identifier, node.RightChild.Value);
Tuple <List <int>[], bool> c2 = FirstLastTable[key];
if (c1.Item2)
{
firsts.AddRange(c1.Item1[0]);
firsts.AddRange(c2.Item1[0]);
}
else
{
firsts.AddRange(c1.Item1[0]);
}
if (c2.Item2)
{
lasts.AddRange(c1.Item1[1]);
lasts.AddRange(c2.Item1[1]);
}
else
{
lasts.AddRange(c2.Item1[1]);
}
if (c1.Item2 && c2.Item2)
{
nullable = true;
}
}
else if (node.Value.Equals("*"))
{
firsts.AddRange(c1.Item1[0]);
lasts.AddRange(c1.Item1[1]);
nullable = true;
}
else if (node.Value.Equals("+"))
{
firsts.AddRange(c1.Item1[0]);
lasts.AddRange(c1.Item1[1]);
}
else
{
firsts.AddRange(c1.Item1[0]);
lasts.AddRange(c1.Item1[1]);
nullable = true;
}
List <int>[] values = new List <int>[2] {
firsts, lasts
};
Tuple <int, string> identifier = new Tuple <int, string>(node.Identifier, node.Value);
Tuple <List <int>[], bool> data = new Tuple <List <int>[], bool>(values, nullable);
FirstLastTable.Add(identifier, data);
}
}
}
