1 SyntaxError:33:Expected l-value but found +
   2 ++ +3
   3    ^
   4 SyntaxError:33:Expected l-value but found -
   5 ++ -7
   6    ^
   7 SyntaxError:33:Expected l-value but found +
   8 -- +2
   9    ^
  10 SyntaxError:33:Expected l-value but found -
  11 -- -8
  12    ^