霍夫曼编码实现的演示程序，从文件读取字符串，单步演示霍夫曼编码的实现。对学习霍夫曼编码有很好的效果-Huffman coding to achieve the demonstration program, the string read from a file, a single-step demonstration of Huffman coding to achieve. Huffman coding of learning have a good effect