哈夫曼树编码解码，在程序中使用树结构，实现哈夫曼树，核心类：树结构类哈夫曼编解码器类；文本处理类；主程序类-Huffman encoding and decoding tree, the tree structure used in the program to achieve Huffman tree, the core categories: tree class class Huffman codec text processing classes main categories