40 columns                              |
>>> Remove after line comment.
// trailing spaces after here:×20×20×20×20
<<<
// trailing spaces after here:
>>> Remove from empty line comment.
//×20×20×20
<<<
//
>>> Preserve inside block comment lines.
/* one×20×20
   two×20
×20×20×20
   three×20×20×20×20
*/×20×20
<<<
/* one×20×20
   two×20
×20×20×20
   three×20×20×20×20
*/
>>> Remove after code.
main() {×20×20
×20
  veryLongExpression    +×20×20×20
  veryLongStatement;×20×20
}×20×20×20×20
<<<
main() {
  veryLongExpression +
      veryLongStatement;
}