private void DeleteCore(TernarySearchTreeNode <T> node, string key, int index)
{
if (node == null || !key.IsIndexValid(index))
{
return;
}
char @char = key[index];
if (@char == node.Char)
{
if (index == key.Length - 1)
{
if (node.IsEos)
{
size--;
node.IsEos = false;
}
node.Value = default(T);
return;
}
DeleteCore(node.Equal, key, index + 1);
}
else if (@char < node.Char)
{
DeleteCore(node.Left, key, index);
}
else
{
DeleteCore(node.Right, key, index);
}
}
private TernarySearchTreeNode <T> SearchCore(TernarySearchTreeNode <T> node, string key, int index)
{
if (node == null || !key.IsIndexValid(index))
{
return(null);
}
char @char = key[index];
if (@char == node.Char)
{
if (index == key.Length - 1)
{
return(node.IsEos ? node : null);
}
return(SearchCore(node.Equal, key, index + 1));
}
else if (@char < node.Char)
{
return(SearchCore(node.Left, key, index));
}
else
{
return(SearchCore(node.Right, key, index));
}
}
public void Insert(string key, T tag)
{
Guard.IsNotNull(key, nameof(key));
if (key.IsEmpty())
{
return;
}
root = InsertCore(root, key, 0, tag);
}
protected override IEnumerator <KeyValuePair <string, T> > CreateEnumerator()
{
Stack <TernarySearchTreeNode <T> > stack = new Stack <TernarySearchTreeNode <T> >();
StringBuilder stringBuilder = new StringBuilder(32);
TernarySearchTreeNode <T> node = root;
while (true)
{
while (node != null)
{
stack.Push(node);
node = node.Left;
}
if (stack.IsEmpty)
{
yield break;
}
node = stack.Peek();
if (node != null)
{
stringBuilder.Append(node.Char);
if (node.IsEos)
{
yield return(new KeyValuePair <string, T>(stringBuilder.ToString(), node.Value));
}
stack.Push(null);
node = node.Equal;
}
else
{
stringBuilder.RemoveLastChar();
stack.Pop();
node = stack.Pop().Right;
}
}
}
private TernarySearchTreeNode <T> InsertCore(TernarySearchTreeNode <T> node, string key, int index, T tag)
{
if (!key.IsIndexValid(index))
{
return(null);
}
if (node == null)
{
node = new TernarySearchTreeNode <T>(key[index]);
}
char @char = key[index];
if (@char == node.Char)
{
if (index == key.Length - 1)
{
if (!node.IsEos)
{
node.IsEos = true;
node.Value = tag;
size++;
}
return(node);
}
node.Equal = InsertCore(node.Equal, key, index + 1, tag);
}
else if (@char < node.Char)
{
node.Left = InsertCore(node.Left, key, index, tag);
}
else
{
node.Right = InsertCore(node.Right, key, index, tag);
}
return(node);
}
public TernarySearchTree()
{
this.size = 0;
this.root = null;
}
