public TrieNode(SupportedCharacters supportedCharacters)
{
if (supportedCharacters == null)
{
throw new ArgumentNullException("supportedCharacters");
}
this.supportedCharacters = supportedCharacters;
children = new TrieNode[supportedCharacters.Count];
}
private void Initialize(IList <string> input)
{
// Identify the set of characters contained in the input
supportedCharacters =
new SupportedCharacters(input.Cast <IEnumerable <char> >().SelectMany(cs => cs));
// Create a node-based trie
var rootNode = new TrieNode(supportedCharacters);
foreach (var str in input)
{
rootNode.Add(str);
}
// Shrink the trie down to an acyclic word graph by sharing common suffixes.
var canonicalNodes = CreateCanonicalNodeDictionary(rootNode);
// Make sure that our array representation can contain the number of nodes
if (canonicalNodes.Count >= byte.MaxValue)
{
throw new InvalidOperationException("Too many nodes - System.Byte may be too small.");
}
// Initialize the array representation of the node structure
trie = new byte[canonicalNodes.Count + 1, supportedCharacters.Count + 1];
// Establish a mapping between canonical nodes an array indices.
var numToNode = new TrieNode[canonicalNodes.Keys.Count + 1];
canonicalNodes.Keys.CopyTo(numToNode, 1); // Leave the first row (number 0) null.
var nodeToNum = new Dictionary <TrieNode, byte>(new NodeToNumComparer());
for (var i = 1; i < numToNode.Length; ++i)
{
nodeToNum.Add(numToNode[i], (byte)i);
}
// Populate the array, and let the garbage collecter handle the object refs.
Fill(rootNode, nodeToNum);
root = nodeToNum[rootNode];
}
