%{#include <stdio.h>/* we found the following required for some yacc implementations. *//* #define YYSTYPE int */%}%token NOUN PRONOUN VERB ADVERB ADJECTIVE PREPOSITION CONJUNCTION%%sentence: simple_sentence   { printf("Parsed a simple sentence.\n"); }	| compound_sentence { printf("Parsed a compound sentence.\n"); }	; simple_sentence: subject verb object	|	subject verb object prep_phrase	;compound_sentence: simple_sentence CONJUNCTION simple_sentence	|	compound_sentence CONJUNCTION simple_sentence	;subject:	NOUN	|	PRONOUN	|	ADJECTIVE subject	;verb:		VERB	|	ADVERB VERB	|	verb VERB	;	object:		NOUN	|	ADJECTIVE object	;prep_phrase:	PREPOSITION NOUN	;%%extern FILE *yyin;main(){	while(!feof(yyin)) {		yyparse();	}}yyerror(s)char *s;{    fprintf(stderr, "%s\n", s);}