%{
  /*C declarations */
#define YYDEBUG 1
%}


%token INTEGER EOL 



%% /* the grammar section */

line: exp EOL { printf("%d\n", $1); }
    ;

exp: exp '+' exp  { $$ = $1 + $3; } 
   | exp '-' exp  { $$ = $1 - $3; }
   | INTEGER      { $$ = $1; }
   ;     



%%
/* as with Flex, user-supplied C code */
/* include the Flex-generated lexical analyzer */
#include "gram7.yy.c"

main()
{
        extern int yydebug;
	extern int yy_flex_debug;
        yydebug = 1; yy_flex_debug = 1;
        yyparse();
}

int yyerror(char *s) {
  fprintf(stderr, "%s\n", s);
  return 0;
}