说明：  哈夫曼编/译码器 需求分析 根据程序目录建立函数，分别为CREATE-建立哈夫曼树，TABLE-输出编码，CODING-编码，DECODING-译码。 CREATE 函数实现从键盘输入字符集中的所有字符及其对应的频率值，建立哈夫曼编码树。 TABLE函数实现利用已建好的哈夫曼树，列出字符集中的所有字符及其对应的哈夫曼编码。 CODING函数实现利用建好哈夫曼树，对从键盘输入的正文串进行编码，并在屏幕上显示结果。 DECODING函数实现利用已建好的哈夫曼树，对从键盘输入的0，1代码串进行译码，并在屏幕上显示结果。
(Huffman encoder/decoder needs analysis in accordance with procedures established directory function, namely the establishment of CREATE-Huffman tree, TABLE-output coding, CODING-coding, DECODING-decoding. CREATE function keyboard input from all the characters in character and its corresponding frequency value, the establishment of Huffman coding tree. TABLE function has been built using Huffman tree, listed in character all the characters and their corresponding Huffman. CODING function built using Huffman tree, keyboard input from the body encoded string, and the result will be displayed on the screen. Decoding function has been built using Huffman tree, from the keyboard input of 0,1 decoding code strings, and the result will be displayed on the screen.)