public class ColorCodes
{
   /**
      Returns the code of the given image when doubled in size
      @param img the codes of an image
      @return the color codes of the doubled image
   */
   public String doubleImage(String img)
   {
      String result = "";
      String buffer = "";
      for (int i = 0; i < img.length(); i++)
      {
          char ch = img.charAt(i);
          if (ch == '\n')
          {
             result += buffer + '\n' + buffer + '\n';
             buffer = "";
          }
          else
          {
             buffer += ch;
             buffer += ch;
          }
      }
      return result;
   }
}