private void BFS(IGraph graph, Int32 sourceVertice)
{
AST.Queue <Int32> queue = new AST.Queue <Int32>();
// We start at source, so we're the shortest path to source.
// Shortest path found.
this._shortestPathToVerticeMap[sourceVertice] = true;
queue.Enqueue(sourceVertice);
while (!queue.IsEmpty)
{
Int32 vertice = queue.Dequeue(); // Remove the next vertice from the queue.
foreach (Int32 adjacentVertice in graph.GetAdjacentVertices(vertice))
{
// For every unmarked adjacent vertice:
// - Save the last vertice that connected to it.
// - Mark the shortest path for the adjacent vertice as found.
// - Add it to the queue to be visied later.
// When no more adjacent vertices are found, start dequeuing vertices
// so we can visit its adjacent vertices.
if (!this._shortestPathToVerticeMap[adjacentVertice])
{
this._edgeTo[adjacentVertice] = vertice;
this._shortestPathToVerticeMap[adjacentVertice] = true;
queue.Enqueue(adjacentVertice);
}
}
}
}
private void GetKeysThatMatch(Node node, StringBuilder prefix, Int32 index, String pattern, AST.Queue <String> queue)
{
if (node == null)
{
return;
}
Char c = pattern[index];
if (c == '.' || c < node.Char)
{
this.GetKeysThatMatch(node.Left, prefix, index, pattern, queue);
}
if (c == '.' || c == node.Char)
{
if (index == pattern.Length - 1 && node.Value != null)
{
queue.Enqueue(prefix.ToString() + node.Char);
}
if (index < pattern.Length - 1)
{
this.GetKeysThatMatch(node.Middle, prefix.Append(node.Char), index + 1, pattern, queue);
prefix.Remove(prefix.Length - 1, 1);
}
}
if (c == '.' || c > node.Char)
{
this.GetKeysThatMatch(node.Right, prefix, index, pattern, queue);
}
}
public IEnumerable <String> GetKeysWithPrefix(String prefix)
{
if (prefix == null)
{
throw new ArgumentNullException(nameof(prefix));
}
AST.Queue <String> queue = new AST.Queue <String>();
Node node = this.Get(this._root, prefix, 0);
if (node == null)
{
return(queue);
}
if (node.Value != null)
{
queue.Enqueue(prefix);
}
this.GetKeysWithPrefix(node.Middle, new StringBuilder(prefix), queue);
return(queue);
}
private void GetKeysWithPrefix(Node node, StringBuilder prefix, AST.Queue <String> queue)
{
if (node == null)
{
return;
}
this.GetKeysWithPrefix(node.Left, prefix, queue);
if (node.Value != null)
{
queue.Enqueue(prefix.ToString() + node.Char);
}
this.GetKeysWithPrefix(node.Middle, prefix.Append(node.Char), queue);
prefix.Remove(prefix.Length - 1, 1);
this.GetKeysWithPrefix(node.Right, prefix, queue);
}
private void GetKeysThatMatch(Node node, StringBuilder prefix, String pattern, AST.Queue <String> results)
{
if (node == null)
{
return;
}
Int32 index = prefix.Length;
if (index == pattern.Length && node.Value != null)
{
results.Enqueue(prefix.ToString());
}
if (index == pattern.Length)
{
return;
}
Char c = pattern[index];
if (c == '.')
{
for (char ch = this.Alphabet.MinChar; ch <= this.Alphabet.MaxChar; ch++)
{
prefix.Append(ch);
this.GetKeysThatMatch(node.Next[ch], prefix, pattern, results);
prefix.Remove(prefix.Length - 1, 1);
}
}
else
{
prefix.Append(c);
this.GetKeysThatMatch(node.Next[c], prefix, pattern, results);
prefix.Remove(prefix.Length - 1, 1);
}
}
private void GetKeysWithPrefix(Node node, StringBuilder prefix, AST.Queue <String> results)
{
if (node == null)
{
return;
}
if (node.Value != null)
{
results.Enqueue(prefix.ToString());
}
for (char c = this.Alphabet.MinChar; c <= this.Alphabet.MaxChar; c++)
{
prefix.Append(c);
this.GetKeysWithPrefix(node.Next[c], prefix, results);
prefix.Remove(prefix.Length - 1, 1);
}
}
