internal static int bdfs(BState s)
{
BTrans t;
BScc c;
BScc scc = new BScc();
scc.bstate = s;
scc.rank = rank;
scc.theta = rank++;
scc.nxt = scc_stack;
scc_stack = scc;
s.incoming = 1;
for (t = s.trans.nxt; t != s.trans; t = t.nxt)
{
if (t.to.incoming == 0)
{
int result = bdfs(t.to);
scc.theta = Math.Min(scc.theta, result);
}
else
{
for (c = scc_stack.nxt; c != null; c = c.nxt)
if (c.bstate == t.to)
{
scc.theta = Math.Min(scc.theta, c.rank);
break;
}
}
}
if (scc.rank == scc.theta)
{
if (scc_stack == scc)
{ /* s is alone in a scc */
s.incoming = -1;
for (t = s.trans.nxt; t != s.trans; t = t.nxt)
if (t.to == s)
s.incoming = 1;
}
scc_stack = scc.nxt;
}
return scc.theta;
}
internal static void simplify_bscc()
{
BState s;
rank = 1;
scc_stack = null;
if (bstates == bstates.nxt) return;
for (s = bstates.nxt; s != bstates; s = s.nxt)
s.incoming = 0; /* state color = white */
bdfs(bstates.prv);
for (s = bstates.nxt; s != bstates; s = s.nxt)
if (s.incoming == 0)
remove_bstate(s, null);
}
