产生一个文件的十六进制倾印码(dump)。它应该从命令行接受单个参数，也就是需要进行倾印的文件名。如果命令行未给出参数，程序就打印标准输入的字符串的倾印码。-Produce a hex dump file code (dump). It should accept the individual arguments from the command line, that is, the need for dump file names. If the command line parameter is not given, the program will print the standard input of string dump code.