该系统应具有以下功能：

（1）　　I：初始化（Initialization）。从终端读入字符集大小n，以及n个字符和n个权值，建立哈夫曼树，并将它存于文件hfmTree中。

（2）　　E：编码（Encoding）。利用已建好的哈夫曼树（如不在内存，则从文件hfmTree中读入），对文件ToBeTran中的正文进行编码，然后将结果存入文件CodeFile中。

（3）　　D：译码（Decoding）。利用已建好的哈夫曼树将文件CodeFile中的代码进行译码，结果存入文件TextFile中。

（4）　　P：打印代码文件（Print）。将文件CodeFile以紧凑格式显示在终端上，每行50个代码。同时将此字符形式的编码文件写入文件CodePrin中。

（5）　　T：打印哈夫曼树（Tree printing）。将已在　　中的哈夫曼树以直观的方式（树或凹入表形式）显示在终端上，同时将此字符形式的哈夫曼树写入文件TreePrint中。

-The system should have the following features: (1) I: initialization (Initialization). Read from the terminal character set size n, and n and n characters right value, establishes a Huffman tree, and save it in the file hfmTree in. (2) E: encoding (Encoding). Has been built using the Huffman tree (if not in memory, reads from the file hfmTree), the text of the document ToBeTran encoded, and then putting the result in the CodeFile file. (3) D: decoding (Decoding). Huffman tree has been built using the file CodeFile the code will be decoded, the result is stored in the file TextFile. (4) P: Printing code files (Print). CodeFile in a compact format the document displayed on the terminal, one per line 50 code. While this character in the form of written documents CodePrin encoded file in. (5) T: Print Huffman tree (Tree printing). Would have been in the Huffman tree in an intuitive way (tree or recessed table form) displayed on the terminal, but this form of characters written to the file