从终端输入字母和相应的频率 在内存中构造Huffman树 从终端输入任意的单词 以二进制形式输出编码后的文字（在屏幕上显示0或1表示相应的位） -Huffman tree constructed in memory from the terminal enter the letters and the corresponding frequency from the terminal to enter any word on the screen text to binary f