public void BuildTree(byte[] source = null)
{
nodes.Clear();
if (source != null) { frequencies.Import(source); }
foreach (KeyValuePair<byte, int> symbol in frequencies.Frequencies)
{
nodes.Add(new Node { Symbol = symbol.Key, Frequency = symbol.Value });
}
while (nodes.Count > 1)
{
List<Node> orderedNodes = nodes.OrderBy(node => node.Frequency).ThenBy(node => node.Symbol).ToList();
if (orderedNodes.Count >= 2)
{
List<Node> takenNodes = orderedNodes.Take(2).ToList();
Node parent = new Node
{
Frequency = takenNodes[0].Frequency + takenNodes[1].Frequency,
Left = takenNodes[0],
Right = takenNodes[1]
};
nodes.Remove(takenNodes[0]);
nodes.Remove(takenNodes[1]);
nodes.Add(parent);
leafCount++;
}
}
root = nodes.FirstOrDefault();
}
private void processNode(Node node, List<bool> data)
{
if (node.Left == null && node.Right == null)
{
if (data.Count == 0) { data.Add(true); data.Add(false); }
data.Add(true); data.Add(true);
byte mask = 0x80;
for (int i = 0; i < 8; i++)
{
data.Add((node.Symbol & mask) == mask);
mask >>= 1;
}
data.Add(false); data.Add(false);
}
else
{
data.Add(true); data.Add(false);
if (node.Left != null) { processNode(node.Left, data); }
if (node.Right != null) { processNode(node.Right, data); }
}
}
