建立一个文本文件A，统计该文件中各字符的频率，对各字符进行Huffman编码，将该文件翻译成Huffman编码文件B，再将Huffman编码文件译码成文件C，并对文件A与C进行比较。

要求：能够对dat、txt等类型文件进行压缩

-The establishment of a text file A, statistics that document the frequency of the characters, the characters of Huffman coding, the Huffman encoding the translation of documents into document B, and then decoding Huffman encoded file into a file C, and a document A and C for comparison. Requirements: able to dat, txt file, such as the type of compression