说明：  Huffman编码是最优变长码，请设计一个Huffma编码程序，实现以下功能： （1）接收原始数据：从终端读入字符集大小n,以及n个字符和权值，建立Huffman 树，并将它文件hfmtree.dat中。 （2）编码：利用已建立的哈夫曼树，对文件中的正文进行编码，将结果存入文件codefile.dat中。 （3）译码：利用已建立号的哈夫曼树将sodefile.dat中的代码进行译码，结果存入文件textfile.dat中。 （4）打印编码规：即字符与编码之间的一一对应关系。 （5）打印Huffman树，将已存入内存中的哈夫曼树以直观的方式显示在终端上。
(Huffman coding is optimal variable-length code, the design of a Huffma coding process, realize the following functions: (1) to receive the raw data: Reading from the terminal into the character set size n, and n characters, and the right values, the establishment of Huffman tree, and It documents in hfmtree.dat. (2) Coding: Using the Huffman tree has been established to document the body encode the results into a document in codefile.dat. (3) Decoding: The number has been established Huffman tree will sodefile.dat decoding of code, resulting in a document deposited in textfile.dat. (4) Print coding rules: that is, characters with one-to-one relationship between the encoding. (5) Print Huffman tree will have been deposited in the Huffman tree in memory intuitive way to show that in the terminal.)