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Hussein39
شنبه 13 خرداد 1391, 18:21 عصر
سلام دوستان
ممکنه بگید که متدTraverseتو کلاس Node چیکار میکنه



using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Collections; namespace HuffmanTest { public class HuffmanTree { private List<Node> nodes = new List<Node>(); public Node Root { get; set; } public Dictionary<char, int> Frequencies = new Dictionary<char, int>(); public void Build(string source) { for (int i = 0; i < source.Length; i++) { if (!Frequencies.ContainsKey(source[i])) { Frequencies.Add(source[i], 0); } Frequencies[source[i]]++; } foreach (KeyValuePair<char, int> symbol in Frequencies) { nodes.Add(new Node() { Symbol = symbol.Key, Frequency = symbol.Value }); } while (nodes.Count > 1) { List<Node> orderedNodes = nodes.OrderBy(node => node.Frequency).ToList<Node>(); if (orderedNodes.Count >= 2) { // Take first two items List<Node> taken = orderedNodes.Take(2).ToList<Node>(); // Create a parent node by combining the frequencies Node parent = new Node() { Symbol = '*', Frequency = taken[0].Frequency + taken[1].Frequency, Left = taken[0], Right = taken[1] }; nodes.Remove(taken[0]); nodes.Remove(taken[1]); nodes.Add(parent); } this.Root = nodes.FirstOrDefault(); } } public BitArray Encode(string source) { List<bool> encodedSource = new List<bool>(); for (int i = 0; i < source.Length; i++) { List<bool> encodedSymbol = this.Root.Traverse(source[i], new List<bool>()); encodedSource.AddRange(encodedSymbol); } BitArray bits = new BitArray(encodedSource.ToArray()); return bits; } public string Decode(BitArray bits) { Node current = this.Root; string decoded = ""; foreach (bool bit in bits) { if (bit) { if (current.Right != null) { current = current.Right; } } else { if (current.Left != null) { current = current.Left; } } if (IsLeaf(current)) { decoded += current.Symbol; current = this.Root; } } return decoded; } public bool IsLeaf(Node node) { return (node.Left == null && node.Right == null); } }


می دونم که symbol و frequency بعنوان دیتا left و right برای ذخیره نود های دیگر هست
کد کامل:


using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Collections; namespace HuffmanTest { public class HuffmanTree { private List<Node> nodes = new List<Node>(); public Node Root { get; set; } public Dictionary<char, int> Frequencies = new Dictionary<char, int>(); public void Build(string source) { for (int i = 0; i < source.Length; i++) { if (!Frequencies.ContainsKey(source[i])) { Frequencies.Add(source[i], 0); } Frequencies[source[i]]++; } foreach (KeyValuePair<char, int> symbol in Frequencies) { nodes.Add(new Node() { Symbol = symbol.Key, Frequency = symbol.Value }); } while (nodes.Count > 1) { List<Node> orderedNodes = nodes.OrderBy(node => node.Frequency).ToList<Node>(); if (orderedNodes.Count >= 2) { // Take first two items List<Node> taken = orderedNodes.Take(2).ToList<Node>(); // Create a parent node by combining the frequencies Node parent = new Node() { Symbol = '*', Frequency = taken[0].Frequency + taken[1].Frequency, Left = taken[0], Right = taken[1] }; nodes.Remove(taken[0]); nodes.Remove(taken[1]); nodes.Add(parent); } this.Root = nodes.FirstOrDefault(); } } public BitArray Encode(string source) { List<bool> encodedSource = new List<bool>(); for (int i = 0; i < source.Length; i++) { List<bool> encodedSymbol = this.Root.Traverse(source[i], new List<bool>()); encodedSource.AddRange(encodedSymbol); } BitArray bits = new BitArray(encodedSource.ToArray()); return bits; } public string Decode(BitArray bits) { Node current = this.Root; string decoded = ""; foreach (bool bit in bits) { if (bit) { if (current.Right != null) { current = current.Right; } } else { if (current.Left != null) { current = current.Left; } } if (IsLeaf(current)) { decoded += current.Symbol; current = this.Root; } } return decoded; } public bool IsLeaf(Node node) { return (node.Left == null && node.Right == null); } }

Direlap
شنبه 13 خرداد 1391, 19:23 عصر
اگه یکم جمع و جورتر کدتون رو بنویسین حداقلش اینه که بهتر خونده میشه . اینطوری بهتر جواب میگیرین .