options { IGNORE_CASE=true; } PARSER_BEGIN(IdS) public class IdS { public static void main(String args[]) throws ParseException { IdS parser = new IdS(System.in); parser.Input(); } } PARSER_END(IdS) SKIP : { " " | "\t" | "\n" | "\r" } TOKEN : { < Id: ["A"-"Z"] ("A"-"Z","0"-"9","_"] )* > } void Input() : {} { ( <Id> )+ <EOF> }