public void gen_dfa(tree t)
{
t.get_leaves(t.root);
//MessageBox.Show(t.leaves.Count.ToString());
int ctr = 1;
dfa r = new dfa();
state beg = new state();
beg.name = t.root.firstpos;
r.begin = beg;
r.states.Add(beg);
Stack <state> steck = new Stack <state>();
String transit = "";
steck.Push(beg);
while (steck.Count > 0)
{
//state dd = new state();
state see = steck.Pop();
foreach (var v in new HashSet <char>(t.leaves.Values))//for all symbols
{
state dd = new state();
foreach (int elem in see.name)
{
if (t.leaves[elem] == v)
{
dd.name.UnionWith(t.followpos[elem - 1]);
//richTextBox1.Text += STR(t.followpos[elem - 1]) + "|||";
}
}
if (v != '#')
{
richTextBox1.Text += "d(" + STR(see.name) + "," + v + ")->" + STR(dd.name) + "\n";
}
bool b = r.states.Add(dd);
if (b)
{
steck.Push(dd);
}
}
}
// richTextBox1.Text += transit;
}
void create_parse_tree(String s)
{
int idctr = 1;
Stack <node> st = new Stack <node>();
foreach (char c in s)
{
if (Char.IsLetterOrDigit(c) || c == '#')
{
node tmp = new node(c);
tmp.ID = idctr;
tmp.lastpos.Add(idctr);
tmp.firstpos.Add(idctr++);
//tmp.left = null; tmp.right = null;
st.Push(tmp);
}
else
{
if (c == '*')
{
node d = st.Pop();
node now = new node(c);
now.firstpos = d.firstpos;
now.lastpos = d.lastpos;
now.left = d;
now.nullable = true;
//richTextBox1.Text += "\n*:"+now.lastpos.Count.ToString() + "_" + now.firstpos.Count.ToString();
st.Push(now);
}
if (c == '|' || c == '+')
{
node n1 = st.Pop();
node n2 = st.Pop();
node now = new node(c);
now.left = n2;
now.right = n1;
now.firstpos.UnionWith(n1.firstpos);
now.firstpos.UnionWith(n2.firstpos);
now.lastpos.UnionWith(n1.lastpos);
now.lastpos.UnionWith(n2.lastpos);
now.nullable = n1.nullable || n2.nullable;
//richTextBox1.Text += "\n|:" + now.lastpos.Count.ToString() + "_" + now.firstpos.Count.ToString();
st.Push(now);
}
if (c == '.')
{
node n1 = st.Pop();
node n2 = st.Pop();
node now = new node(c);
now.left = n2;
now.right = n1;
now.nullable = n1.nullable && n2.nullable;
if (n2.nullable)
{
now.firstpos.UnionWith(n1.firstpos);
now.firstpos.UnionWith(n2.firstpos);
}
else
{
now.firstpos.UnionWith(n2.firstpos);
}
if (n1.nullable)
{
now.lastpos.UnionWith(n1.lastpos);
now.lastpos.UnionWith(n2.lastpos);
}
else
{
now.lastpos.UnionWith(n1.lastpos);
}
//richTextBox1.Text += "\n.:" + now.lastpos.Count.ToString() + "_" + now.firstpos.Count.ToString();
st.Push(now);
}
}
}
tree tr = new tree(st.Pop());
tr.inorder(tr.root);
tr.followpos = new HashSet <int> [idctr - 1];
for (int p = 0; p < idctr - 1; p++)
{
tr.followpos[p] = new HashSet <int>();
}
tr.follow_pos(tr.root);
// MessageBox.Show((idctr - 1).ToString());
Console.WriteLine();
richTextBox1.Text += "\nfirstpos of root: ";
foreach (int x in tr.root.firstpos)
{
richTextBox1.Text += x.ToString() + "_";
}
richTextBox1.Text += "\nendpos of root: ";
foreach (int x in tr.root.lastpos)
{
richTextBox1.Text += x.ToString() + "_";
}
String fol = "";
for (int h = 0; h < tr.followpos.Length; h++)
{
fol += "\nfollowpos(" + (h + 1) + ")=";
foreach (var set in tr.followpos[h])
{
fol += set + ",";
}
}
richTextBox1.Text += fol + "\n";
gen_dfa(tr);
}