利用Object—C语言编写一个统计字符串长度的程序，病毒写到相应文件中-Using Object-C language string length of a statistical procedure, the virus writes the corresponding file

包含有统计字符串中各个字符的个数，冒泡升序排序，求huffman编码-Contains statistical string of different characters in number, bubbling ascending order, for Huffman coding