/// <summary>
/// Builds the Huffman tree
/// </summary>
/// <param name="source">The source to build the Hufftree from</param>
/// <exception cref="ArgumentNullException">Thrown when source is null or empty</exception>
public void BuildTree(string source)
{
if (string.IsNullOrEmpty(source))
{
throw new ArgumentNullException("source");
}
Frequencies.Accept(source);
BuildTree();
}
public void Accept(IFeedVisitor visitor)
{
Agencies.Accept(visitor);
Stops.Accept(visitor);
Routes.Accept(visitor);
Trips.Accept(visitor);
StopTimes.Accept(visitor);
Calendars.Accept(visitor);
CalendarDates.Accept(visitor);
FareAttributes.Accept(visitor);
FareRules.Accept(visitor);
Shapes.Accept(visitor);
Frequencies.Accept(visitor);
Transfers.Accept(visitor);
FeedInfos.Accept(visitor);
}
public void Accept(IFeedVisitor visitor)
{
Parallel.Invoke(
() => Agencies.Accept(visitor),
() => Stops.Accept(visitor),
() => Routes.Accept(visitor),
() => Trips.Accept(visitor),
() => StopTimes.Accept(visitor),
() => Calendars.Accept(visitor),
() => CalendarDates.Accept(visitor),
() => FareAttributes.Accept(visitor),
() => FareRules.Accept(visitor),
() => Shapes.Accept(visitor),
() => Frequencies.Accept(visitor),
() => Transfers.Accept(visitor),
() => FeedInfos.Accept(visitor)
);
}
/// <summary>
/// Builds the Huffman tree
/// </summary>
/// <param name="source">The source to build the Hufftree from</param>
/// <exception cref="ArgumentNullException">Thrown when source is null or empty</exception>
public void BuildTree(string source)
{
nodes.Clear(); //As we build a new tree, first make sure it's clean :)
if (string.IsNullOrEmpty(source))
{
throw new ArgumentNullException("source");
}
else
{
Frequencies.Accept(source);
foreach (KeyValuePair <char, int> symbol in Frequencies.FrequencyTable)
{
nodes.Add(new HuffmanNode()
{
Character = symbol.Key, Frequency = symbol.Value
});
}
while (nodes.Count > 1)
{
List <HuffmanNode> orderedNodes = nodes.OrderBy(node => node.Frequency).ToList();
if (orderedNodes.Count >= 2)
{
List <HuffmanNode> takenNodes = orderedNodes.Take(2).ToList();
HuffmanNode parent = new HuffmanNode()
{
Character = null,
Frequency = takenNodes[0].Frequency + takenNodes[1].Frequency,
Left = takenNodes[0],
Right = takenNodes[1]
};
//Remove the childnodes from the original node list and add the new parent node
nodes.Remove(takenNodes[0]);
nodes.Remove(takenNodes[1]);
nodes.Add(parent);
}
}
Root = nodes.FirstOrDefault();
}
}
