C++ class实现Huffman树(完整代码)

在这里插入图片描述

代码如下:

#include <iostream>
#include <string>
using namespace std;
const unsigned int n = 8;//字符数NUM，这里的字符数为8
const unsigned int m = 2 * n - 1;//结点总数
const float MAX = 1e8;class HTNode
{friend class HuffmanTree;
private:float weight;int parent;int lchild;int rchild;
};class HuffmanTree
{
public:HuffmanTree();~HuffmanTree() = default;void PrintCode();
private:void DFS(int i, int step);void Select(int k, int  &s1, int  &s2);HTNode HT[m + 1];int code[m + 1];
};HuffmanTree::HuffmanTree()
{int s1, s2;for (int i = 1; i <= m; i++){HT[i].weight = 0;HT[i].parent = -1;HT[i].lchild = -1;HT[i].rchild = -1;}cout << "Please input the weight" << endl;for (int i = 1; i <= n; i++)cin >> HT[i].weight;for (int i = n + 1; i <= m; i++){Select(i - 1, s1, s2);HT[s1].parent = i;HT[s2].parent = i;HT[i].lchild = s1;HT[i].rchild = s2;HT[i].weight = HT[s1].weight + HT[s2].weight;cout << HT[i].weight << " " << "(" << HT[s1].weight << "," << HT[s2].weight << ")" << endl;//该输出为测试数据使用}
}void HuffmanTree::Select(int k, int &s1, int &s2)
{HT[0].weight = MAX;s1 = s2 = 0;for (int i = 1; i <= k; i++)if (HT[i].weight != 0 && HT[i].parent == -1){if (HT[i].weight < HT[s1].weight){s2 = s1;s1 = i;}elseif (HT[i].weight < HT[s2].weight) s2 = i;}
}void HuffmanTree::DFS(int i,int step)
{if (HT[i].lchild == -1 && HT[i].rchild == -1){cout << HT[i].weight << " = ";for (int i = 0; i < step; i++)cout << code[i];cout << endl;return;}if (HT[i].lchild != -1 ){code[step] = 0;DFS(HT[i].lchild,step+1);}if (HT[i].rchild != -1 ){code[step] = 1;DFS(HT[i].rchild, step+1);}
}void HuffmanTree::PrintCode()
{for (int i = 0; i < m + 1; i++) code[i] = false;DFS(m, 0);
}int main()
{HuffmanTree t;cout << endl;t.PrintCode();return 0;
}

测试结果:
在这里插入图片描述

动态内存分配写法:

#include <iostream>
using namespace std;
const int MAX = 1e8;class HuffmanNode
{friend class HuffmanTree;
private:double w;int par;int lch;int rch;
};class HuffmanTree
{friend class HuffmanTree;
public:HuffmanTree() ;~HuffmanTree();void PrintCode();
private:void dfs(int i,int s);void Select(int n, int &s1, int &s2);HuffmanNode *HT;int *path;int m;
};void HuffmanTree::Select(int n, int &s1, int &s2)
{s1 = s2 = 0;HT[0].w = MAX;for (int i = 1; i <= n; i++){if (HT[i].par==-1 && HT[i].w!=0)if (HT[i].w < HT[s1].w){s2 = s1;s1 = i;}elseif (HT[i].w < HT[s2].w) s2 = i;}
}HuffmanTree::HuffmanTree() :HT(nullptr), path(nullptr)
{cout << "Please input node:" << endl;int n;cin >> n;m = 2 * n - 1;HT = new HuffmanNode[m + 1];for (int i = 1; i <= m; i++){HT[i].par = -1;HT[i].lch = -1;HT[i].rch = -1;HT[i].w = 0;}for (int i = 1; i <= n; i++) cin >> HT[i].w;for (int i = n + 1; i <= m; i++){int s1, s2;Select(i - 1, s1, s2);HT[s1].par = i;HT[s2].par = i;HT[i].lch = s1;HT[i].rch = s2;HT[i].w = HT[s1].w + HT[s2].w;cout << HT[i].w << " " << "(" << HT[s1].w << "," << HT[s2].w << ")" << endl;}
}void HuffmanTree::dfs(int i,int s)
{if (HT[i].lch == -1 && HT[i].rch == -1){cout << HT[i].w << " = ";for (int i = 0; i < s; i++) cout << path[i];cout << endl;return;}if (HT[i].lch != -1){path[s] = 0;dfs(HT[i].lch, s + 1);}if (HT[i].rch != -1){path[s] = 1;dfs(HT[i].rch, s + 1);}
}void HuffmanTree::PrintCode()
{path = new int[m + 1];for (int i = 0; i < m + 1; i++) path[i] = 0;dfs(m,0);delete[]path;path = nullptr;
}HuffmanTree::~HuffmanTree()
{delete[] HT;HT = nullptr;
}int main()
{HuffmanTree t;t.PrintCode();return 0;
}