C语言十六进制数转八进制（十进制作为中介）(附完整源码)

C语言十六进制数转八进制完整源码

#include <stdio.h>  /// for printf() and fgets()
#include <string.h> /// for memset()

/**
 * @brief Convert a hexadecimal number to octal number.
 * @param hex Hexadecimal number to convert.
 * @returns A pointer to the converted octal string.
 */
const char