private int[] FindSmall(HuffmanTree <T>[] forest) //找到森林中权值最小的两棵树
{
int[] result = new int[2];
HuffmanTree <T>[] temp = new HuffmanTree <T> [forest.Length];
for (int i = 0; i < temp.Length; i++)
{
temp[i] = forest[i];
}
for (int i = 0; i < temp.Length; i++)
{
for (int j = i; j > 0; j--)
{
if (temp[j].root.Weight < temp[j - 1].root.Weight)
{
HuffmanTree <T> temp1 = temp[j];
temp[j] = temp[j - 1];
temp[j - 1] = temp1;
}
}
}
int x = temp[0].root.Weight, y = temp[1].root.Weight;
for (int i = 0; i < forest.Length; i++)
{
if (forest[i].root.Weight == x)
{
result[0] = i;
}
}
for (int i = 0; i < forest.Length; i++)
{
if (forest[i].root.Weight == y && i != result[0])
{
result[1] = i;
}
}
return(result);
}
private HuffmanTree <char> BuildTree() //建立Huffman树
{
char[] temp = message.ToCharArray();
char[] letter1 = new char[temp.Length];
int k = 0;
for (int i = 0; i < temp.Length; i++)
{
if (Contain(letter1, temp[i]) == 0)
{
letter1[k] = temp[i];
k++;
}
}
int num = 0;
for (int i = 0; i < letter1.Length; i++)
{
if (letter1[i] != '\0')
{
num++;
}
}
char[] letter = new char[num];
int[] weight = new int[num];
for (int i = 0; i < letter.Length; i++)
{
letter[i] = letter1[i];
}
for (int i = 0; i < weight.Length; i++)
{
weight[i] = Contain(temp, letter[i]);
}
HuffmanTree <char> codeTree = new HuffmanTree <char>(letter, weight);
return(codeTree);
}
private HuffmanTree <T>[] ClearNull(HuffmanTree <T>[] forest) //清除森林中空树
{
int x = 0;
for (int i = 0; i < forest.Length; i++)
{
if (forest[i] != null)
{
x++;
}
}
HuffmanTree <T>[] result = new HuffmanTree <T> [x];
int y = 0;
for (int i = 0; i < forest.Length; i++)
{
if (forest[i] != null)
{
result[y] = forest[i];
y++;
}
}
return(result);
}
public HuffmanTree(T[] data, int[] weight) //唯一构造
{
if (data.Length != weight.Length)
{
Console.WriteLine("输入数据数组与权值数组长度不同！");
}
else
{
HuffmanTree <T>[] forest = new HuffmanTree <T> [data.Length];
int leng = forest.Length;
for (int i = 0; i < forest.Length; i++)
{
forest[i] = new HuffmanTree <T>();
forest[i].root = new HuffmanTreeNode <T>(data[i], weight[i]);
}
for (int i = 0; i < leng - 1; i++)
{
int x = FindSmall(forest)[0], y = FindSmall(forest)[1];
HuffmanTree <T> temp1 = forest[x];
HuffmanTree <T> temp2 = forest[y];
forest[x] = null;
forest[y] = null;
HuffmanTree <T> newtree = new HuffmanTree <T>(default(T), temp1.root.Weight + temp2.root.Weight);
if (temp1.root.Weight < temp2.root.Weight)
{
newtree.root.LeftChild = temp1.root;
newtree.root.RightChild = temp2.root;
}
else if (temp1.root.Weight > temp2.root.Weight)
{
newtree.root.LeftChild = temp2.root;
newtree.root.RightChild = temp1.root;
}
else
{
if (GetHeight(temp1.root) < GetHeight(temp2.root))
{
newtree.root.LeftChild = temp1.root;
newtree.root.RightChild = temp2.root;
}
else if (GetHeight(temp1.root) > GetHeight(temp2.root))
{
newtree.root.LeftChild = temp2.root;
newtree.root.RightChild = temp1.root;
}
else
{
if (x < y)
{
newtree.root.LeftChild = temp1.root;
newtree.root.RightChild = temp2.root;
}
else
{
newtree.root.LeftChild = temp2.root;
newtree.root.RightChild = temp1.root;
}
}
}
forest[x] = newtree;
forest = ClearNull(forest);
}
root = forest[0].root;
FindParent();
}
}
public HuffmanCode(string xx)
{
message = xx;
codeTree = BuildTree();
}
