/// <summary>
/// Looks up a key value in the trie.
/// </summary>
/// <param name="key">The key to look up.</param>
/// <returns>The exact matching <see cref="BinaryTrieNode"/> in the trie.</returns>
public BinaryTrieNode FindExactMatch(Int32 key)
{
if ((key ^ _key) == 0)
{
return(this);
}
// Pick the child to investigate.
if ((key & _bit[_keyLength + 1]) == 0)
{
// If the key matches the child's key, pass on the request.
if (null != _zero)
{
if ((key ^ _zero._key) < _bit[_zero._keyLength])
{
return(_zero.FindExactMatch(key));
}
}
}
else
{
// If the key matches the child's key, pass on the request.
if (null != _one)
{
if ((key ^ _one._key) < _bit[_one._keyLength])
{
return(_one.FindExactMatch(key));
}
}
}
// If we got here, neither child was a match, so the current
// node is the best match.
return(null);
}
/// <summary>
/// Finds the exact internal match for a key.
/// </summary>
/// <param name="index">
/// The index of the root <see cref="BinaryTrieNode"/> for the given key value.
/// </param>
/// <param name="key">An <see cref="Int32"/> key value.</param>
/// <returns>A reference to the <see cref="Object"/> containing the key.</returns>
protected Object FindExactMatchInternal(Int32 index, Int32 key)
{
BinaryTrieNode root = _roots[index];
if (null == root)
{
return(null);
}
return(root.FindExactMatch(key).UserData);
}
