     IO.puts("  symmetric_difference -t : red:yellow:green red:green:blue")
     IO.puts("  symmetric_difference -s '1, 3, 5, 7, 9' '2, 3, 5, 7'")
     IO.puts("  symmetric_difference -s '1, 2, 3, 5, 8' '1, 4, 9' '2, 4, 8' '1, 3, 5, 7, 9' '2, 3, 5, 7'")
+    IO.puts("  symmetric_difference -s -o '1, 2, 3, 5, 8' '1, 4, 9' '2, 4, 8' '1, 3, 5, 7, 9' '2, 3, 5, 7'")
     IO.puts("  symmetric_difference -b")
     IO.puts("  symmetric_difference -b -x 5000000 -c 100")
   end

    IO.puts("    -c          : operate on sets of characters instead of sets of strings")
    IO.puts("    --strip     : strip leading and trailing whitespace from set items")
    IO.puts("    -s          : strip leading and trailing whitespace from set items")
    IO.puts("    --benchmark : perform algorithm benchmark")
    IO.puts("    -b          : perform algorithm benchmark")
    IO.puts("    --max       : benchmark range max, default 1000000")

      t: :token,
      c: :character,
      s: :strip,
      o: :original,
      b: :benchmark,
      x: :max,
      n: :count,
