------------------------------------------------------------------------------------------------------说明：    There are two kinds of comments.    • /* text */        A traditional comment: all the text from the ASCII characters /* to the ASCII characters */ is ignored (as in C and C++).    • // text        An end-of-line comment: all the text from the ASCII characters // to the end of the line is ignored (as in C++).-------------------------------------------------------------------------------------------------------文法:            Comment:         TraditionalComment         EndOfLineComment    TraditionalComment:         / * CommentTail    EndOfLineComment:        // CharactersInLine opt    CommentTail:        * CommentTailStar        NotStar CommentTail    CommentTailStar:         /        * CommentTailStar         NotStarNotSlash CommentTail    NotStar:        InputCharacter but not * LineTerminator    NotStarNotSlash:         InputCharacter but not * or /         LineTerminator    CharactersInLine:        InputCharacter        CharactersInLine InputCharacter    说明:        These productions imply all of the following properties:        • Comments do not nest.        • /* and */ have no special meaning in comments that begin with //.        • // has no special meaning in comments that begin with /* or /**.        As a result, the text:            /* this comment /* // /** ends here: */        is a single complete comment.        The lexical grammar implies that comments do not occur within character literals (§3.10.4) or string literals (§3.10.5).