给定一篇用于通信的英文电文，统计该电文中每个字符出现的频率，按频率左小右大的方法为这些字符建立哈夫曼(Huffamn)树，并编出每个字符的哈夫曼树码，输出该电文的哈夫曼码译文。-English messages for communication to set a statistical frequency of occurrence for each character in the message, according to the frequency of left-right metho