private static void Main()
{
var inputString = Console.ReadLine();
var decodingTable = new Dictionary <char, bool[]>();
var huffmanTree = new TreeRoot();
Encode(inputString, ref decodingTable, ref huffmanTree);
Console.WriteLine($"Input String: {inputString}\n\nTree:");
PrintTree(huffmanTree);
Console.WriteLine("\nDecoding Table:");
PrintDecodingTable(decodingTable);
}
public static void Encode(string input,
ref Dictionary <char, bool[]> decodingTable,
ref TreeRoot tree)
{
// build priority queue
var priorityQueue = new PriorityQueue <TreeNode>();
// first item in tuple is count, second is priority
var chars = new Dictionary <char, (int, int)>();
foreach (var c in input)
{
if (chars.ContainsKey(c))
{
chars[c] = (chars[c].Item1 + 1, chars[c].Item2 + 1);
}
else
{
chars[c] = (1, 1);
}
}
// conflicts :P
while (chars.Any(p => chars.Count(o => o.Value == p.Value) > 1))
{
foreach (var(c, p) in chars)
{
if (chars.Count(o => o.Value.Item2 == p.Item2) > 1)
{
chars[c] = (chars[c].Item1, chars[c].Item2 + 1);
}
}
}
foreach (var(c, i) in chars)
{
priorityQueue.Enqueue((input.Length - i.Item2) * 2,
new TreeNode
{
Character = c,
Count = i.Item1
});
}
// convert flat queue into tree
while (priorityQueue.Count > 1)
{
var low1 = priorityQueue.Dequeue();
var low2 = priorityQueue.Dequeue();
var node = new TreeNode
{
Left = low1,
Right = low2,
Count = low1.Count + low2.Count
};
priorityQueue.Enqueue(input.Length * input.Length - (low1.Count + low2.Count), node);
}
// extract tree
tree = (TreeRoot)priorityQueue.Dequeue();
// build decoding table
var route = new List <bool>();
EncodeTraverseTree(tree, ref decodingTable, ref route);
}
private static void PrintTree(TreeRoot root)
{
((TreeNode)root).Left?.PrintTree("");
// ReSharper disable once TailRecursiveCall
((TreeNode)root).Right?.PrintTree("", true);
}