private bool SearchRecursively(HybridTrieNode node, char[] key, int position)
{
if (node == null)
{
return(false);
}
if (key[position] < node.Character)
{
return(SearchRecursively(node.LeftChild, key, position));
}
else if (key[position] > node.Character)
{
return(SearchRecursively(node.RightChild, key, position));
}
else
{
if (position < key.Length - 1)
{
return(SearchRecursively(node.MiddleChild, key, position + 1));
}
else
{
return(node.IsFinalNode());
}
}
}
// Helper method for {@link #removeRecursively()}.
// Find the successor's parent
private HybridTrieNode FindSuccessorParent(HybridTrieNode successor)
{
HybridTrieNode parent = null;
HybridTrieNode node = Root;
while (node != null)
{
if (successor.Character < node.Character)
{
parent = node;
node = node.LeftChild;
}
else if (successor.Character > node.Character)
{
parent = node;
node = node.RightChild;
}
else
{
if (node.Id.Equals(successor.Id))
{
break;
}
parent = node;
node = node.MiddleChild;
}
}
return(parent);
}
private HybridTrieNode InsertRecursively(HybridTrieNode node, char[] key, int position)
{
if (node == null)
{
node = new HybridTrieNode(key[position]);
}
if (key[position] < node.Character)
{
// Go left, if current character smaller than character of current node.
node.LeftChild = InsertRecursively(node.LeftChild, key, position);
}
else if (key[position] > node.Character)
{
// Go right, if current character greater than character of current node.
node.RightChild = InsertRecursively(node.RightChild, key, position);
}
else
{
if (position < key.Length - 1)
{
// Go middle, if current character equal to node character (If we don't exceed the key).
node.MiddleChild = InsertRecursively(node.MiddleChild, key, position + 1);
}
else if (!node.IsFinalNode())
{
node.MakeFinalNode(1);
}
}
return(node);
}
private int CountPrefixRecursively(HybridTrieNode node, char[] key, int position)
{
if (node == null)
{
return(0);
}
if (key[position] < node.Character)
{
return(CountPrefixRecursively(node.LeftChild, key, position));
}
else if (key[position] > node.Character)
{
return(CountPrefixRecursively(node.RightChild, key, position));
}
else
{
if (position < key.Length - 1)
{
return(CountPrefixRecursively(node.MiddleChild, key, position + 1));
}
else
{
if (node.MiddleChild == null)
{
return(1);
}
else
{
return(CountWords(node.MiddleChild) + (node.IsFinalNode() ? 1 : 0));
}
}
}
}
public void InsertBalanced(string word)
{
if (String.IsNullOrEmpty(word))
{
throw new ArgumentException("Inserting word balanced", "Word can't be null or empty!");
}
Root = InsertBalancedRecursively(Root, word.ToCharArray(), 0);
}
private HybridTrieNode RotateWithRight(HybridTrieNode nodeX)
{
HybridTrieNode nodeY = nodeX.RightChild;
nodeX.RightChild = nodeY.LeftChild;
nodeY.LeftChild = nodeX;
return(nodeY);
}
// Helper method for {@link #CountPrefixRecursively()}.
// Counting all the stored words for a given node.
private int CountWords(HybridTrieNode node)
{
if (IsEmpty())
{
return(0);
}
return(CountWordsRecursively(node, 0));
}
// Helper method for {@link #RemoveRecursively()}.
// Find the successor (in in-order traversal) in the right child.
private HybridTrieNode FindSuccessor(HybridTrieNode node)
{
if (node.LeftChild == null)
{
return(node);
}
else
{
return(FindSuccessor(node.LeftChild));
}
}
private int CountNodesRecursively(HybridTrieNode node, int nodeCount)
{
if (node != null)
{
nodeCount++;
nodeCount = CountNodesRecursively(node.LeftChild, nodeCount);
nodeCount = CountNodesRecursively(node.RightChild, nodeCount);
nodeCount = CountNodesRecursively(node.MiddleChild, nodeCount);
}
return(nodeCount);
}
private int CountNullRecursively(HybridTrieNode node, int nullCounter)
{
if (node != null)
{
nullCounter = CountNullRecursively(node.LeftChild, nullCounter);
nullCounter = CountNullRecursively(node.RightChild, nullCounter);
nullCounter = CountNullRecursively(node.MiddleChild, nullCounter);
}
else
{
nullCounter++;
}
return(nullCounter);
}
private int CountWordsRecursively(HybridTrieNode node, int wordsCounter)
{
if (node != null)
{
if (node.IsFinalNode())
{
wordsCounter++;
}
wordsCounter = CountWordsRecursively(node.LeftChild, wordsCounter);
wordsCounter = CountWordsRecursively(node.RightChild, wordsCounter);
wordsCounter = CountWordsRecursively(node.MiddleChild, wordsCounter);
}
return(wordsCounter);
}
// Helper method for {@link #GetAverageDepthOfLeaves()}.
// Returns the node count for a given node by regarding the node itself and all of
// its successors.
private int CountTotalLeafRecursively(HybridTrieNode node, int leavesCounter)
{
if (node != null)
{
if (!node.HasChildren())
{
leavesCounter++;
}
leavesCounter = CountTotalLeafRecursively(node.LeftChild, leavesCounter);
leavesCounter = CountTotalLeafRecursively(node.RightChild, leavesCounter);
leavesCounter = CountTotalLeafRecursively(node.MiddleChild, leavesCounter);
}
return(leavesCounter);
}
private HybridTrieNode InsertBalancedRecursively(HybridTrieNode node, char[] key, int position)
{
if (node == null)
{
node = new HybridTrieNode(key[position]);
}
if (key[position] < node.Character)
{
node.LeftChild = InsertBalancedRecursively(node.LeftChild, key, position);
if (node.LeftChild.Priority > node.Priority)
{
node = RotateWithLeft(node);
}
}
else if (key[position] > node.Character)
{
node.RightChild = InsertBalancedRecursively(node.RightChild, key, position);
if (node.RightChild.Priority > node.Priority)
{
node = RotateWithRight(node);
}
}
else
{
if (position < key.Length - 1)
{
node.MiddleChild = InsertBalancedRecursively(node.MiddleChild, key, position + 1);
}
else if (!node.IsFinalNode())
{
node.MakeFinalNode(RandomUnique.Number);
}
if (node.MiddleChild == null)
{
node.Priority = node.StringPriority;
}
else
{
node.Priority = Max(node.StringPriority, node.MiddleChild.Priority);
}
}
return(node);
}
private int CalculateHeightRecursively(HybridTrieNode node, int heightCounter, int heightResult)
{
if (node != null)
{
heightCounter++;
heightResult = CalculateHeightRecursively(node.LeftChild, heightCounter, heightResult);
if (heightCounter > heightResult && node.IsFinalNode())
{
heightResult = heightCounter;
}
heightResult = CalculateHeightRecursively(node.RightChild, heightCounter, heightResult);
heightResult = CalculateHeightRecursively(node.MiddleChild, heightCounter, heightResult);
}
return(heightResult);
}
// Helper method for {@link #GetAverageDepthOfLeaves()}.
private int CountTotalLeafDepthRecursively(HybridTrieNode node, int depthCounter, int totalDepth)
{
if (node != null)
{
depthCounter++;
if (!node.HasChildren())
{
totalDepth += depthCounter;
}
totalDepth = CountTotalLeafDepthRecursively(node.LeftChild, depthCounter, totalDepth);
totalDepth = CountTotalLeafDepthRecursively(node.RightChild, depthCounter, totalDepth);
totalDepth = CountTotalLeafDepthRecursively(node.MiddleChild, depthCounter, totalDepth);
}
return(totalDepth);
}
private void PrintRecursively(HybridTrieNode previousNode, HybridTrieNode nextNode, Color color, GraphPrinter graphPrinter)
{
if (nextNode != null)
{
if (previousNode != null)
{
if (color.Equals(Color.BLUE))
{
graphPrinter.PrintEdge(previousNode, nextNode, Color.BLUE);
}
else if (color.Equals(Color.RED))
{
graphPrinter.PrintEdge(previousNode, nextNode, Color.RED);
}
else if (color.Equals(Color.GREEN))
{
graphPrinter.PrintEdge(previousNode, nextNode, Color.GREEN);
}
if (nextNode.IsFinalNode())
{
if (color.Equals(Color.BLUE))
{
graphPrinter.PrintNode(nextNode, Color.BLUE, Color.BLUE, Style.DASHED);
}
else if (color.Equals(Color.RED))
{
graphPrinter.PrintNode(nextNode, Color.RED, Color.RED, Style.DASHED);
}
else if (color.Equals(Color.GREEN))
{
graphPrinter.PrintNode(nextNode, Color.GREEN, Color.GREEN, Style.DASHED);
}
}
graphPrinter.PrintNodeLabel(nextNode);
}
PrintRecursively(nextNode, nextNode.LeftChild, Color.BLUE, graphPrinter);
PrintRecursively(nextNode, nextNode.MiddleChild, Color.RED, graphPrinter);
PrintRecursively(nextNode, nextNode.RightChild, Color.GREEN, graphPrinter);
}
}
private List <string> ListWordsRecursively(HybridTrieNode node, String word, List <String> listWords)
{
if (node != null)
{
ListWordsRecursively(node.LeftChild, word, listWords);
word += node.Character;
if (node.IsFinalNode())
{
listWords.Add(word);
}
ListWordsRecursively(node.MiddleChild, word, listWords);
word = RemoveLastCaracter(word);
ListWordsRecursively(node.RightChild, word, listWords);
}
return(listWords);
}
// Helper method for {@link #RemoveRecursively()}.
// Make a link between a parent node and its child's successor node.
private void Transplant(HybridTrieNode parent, HybridTrieNode node, HybridTrieNode successor)
{
if (parent == null)
{
Root = successor;
}
else if (node == parent.LeftChild)
{
parent.LeftChild = successor;
}
else if (node == parent.RightChild)
{
parent.RightChild = successor;
}
else
{
parent.MiddleChild = successor;
}
}
public void RemoveAll()
{
Root = null;
}
public HybridTrie()
{
Root = null;
}
public HybridTrie(HybridTrieNode root)
{
this.Root = root;
}
private bool RemoveRecursively(HybridTrieNode parent, HybridTrieNode node, char[] key, int position)
{
if (node == null)
{
return(false);
}
var log = true;
if (key[position] < node.Character)
{
log = RemoveRecursively(node, node.LeftChild, key, position);
}
else if (key[position] > node.Character)
{
log = RemoveRecursively(node, node.RightChild, key, position);
}
else
{
// If we are on our last character.
if (position == key.Length - 1)
{
if (node.IsFinalNode())
{
// The node is an end node, remove the end value.
node.MakeFinalNode(0);
}
else
{
// If there is no end key as it does not exist within the tree.
return(false);
}
}
else if (position < key.Length + 1)
{
log = RemoveRecursively(node, node.MiddleChild, key, position + 1);
}
}
// Only remove if the node's middle child is null and if the node is not an end key.
// If log is false, the value has never been found. Thus the key does not exist within this tree.
if (log && node.MiddleChild == null && !node.IsFinalNode())
{
// Case 1: No children, safe to delete.
if (!node.HasChildren())
{
Transplant(parent, node, null);
}
// Case 2: Right is null, transplant it to left.
else if (node.RightChild == null)
{
Transplant(parent, node, node.LeftChild);
}
// Case 3: Left is null, transplant it to right.
else if (node.LeftChild == null)
{
Transplant(parent, node, node.RightChild);
}
// Case 4: Both left and right children exists, find successor and transplant.
else
{
HybridTrieNode successor = FindSuccessor(node.RightChild);
HybridTrieNode successorParent = FindSuccessorParent(successor);
// If successor node has left child(ren).
if (successorParent != node)
{
Transplant(parent, node, node.RightChild);
}
else
{
Transplant(parent, node, successor);
}
// Make the node's left child as left child for successor node.
successor.LeftChild = node.LeftChild;
}
node = null;
}
return(log);
}
