%{
#define YYERROR_VERBOSE
void yyerror(char *);
%}
%verbose
%token COMMAND ID KEYWORD ILLEGAL_CHAR
%%
rule:             COMMAND '(' KEYWORD ')' '(' ID ')'
                | COMMAND '(' ID ')'
                ;
%%
void yyerror(char *msg) {
    printf("\n%s\n", msg);
}
int main() {
    return yyparse();
}