# File lib/rchardet/chardistribution.rb, line 150
    def get_order(aStr)
      # for GB2312 encoding, we are interested 
      #  first  byte range: 0xb0 -- 0xfe
      #  second byte range: 0xa1 -- 0xfe
      # no validation needed here. State machine has done that
      if (aStr[0..0] >= "\xB0") and (aStr[1..1] >= "\xA1")
        return 94 * (aStr[0] - 0xB0) + aStr[1] - 0xA1
      else
        return -1
      end
    end