/// <summary>
///
/// </summary>
/// <param name="text">主串</param>
public void Match(string text)
{
int n = text.Length;
AcNode p = root;
for (int i = 0; i < n; i++)
{
int idx = text[i] - 'a';
while (p.children[idx] == null && p != root)
{
p = p.fail; //失败指针发挥作用的地方
}
p = p.children[idx];
if (p == null)
{
p = root; //没有匹配，从 root 开始重新匹配
}
AcNode tmp = p;
while (tmp != root)
{
if (tmp.IsEndingChar == true)
{
int pos = i - tmp.length + 1;
Console.WriteLine(" 匹配起始下标 " + pos + "; 长度 " + tmp.length);
}
tmp = tmp.fail;
}
}
}
public void BuildFailurePointer()
{
Queue <AcNode> queue = new Queue <AcNode>();
root.fail = null;
queue.Enqueue(root);
while (!(queue.Count == 0))
{
AcNode p = queue.Dequeue();
for (int i = 0; i < 26; ++i)
{
AcNode pc = p.children[i];
if (pc == null)
{
continue;
}
if (p == null)
{
pc.fail = root;
}
else
{
AcNode q = p.fail;
while (q != null)
{
AcNode qc = q.children[pc.Data - 'a'];
if (qc != null)
{
pc.fail = qc;
break;
}
q = q.fail;
}
if (q == null)
{
pc.fail = root;
}
}
queue.Enqueue(pc);
}
}
}
public AcAutomata()
{
root = new AcNode('/');
}
