%{
using namespace std;
#include <iostream>
#include <cstdlib>
extern int line_num;
void yyerror(char*);
int yylex();
%}

%token WITH_tok
%token PERIOD_tok
%token PIZZA_tok
%token SANDWICH_tok
%token ICE_CREAM_tok
%token AND_tok
%token PEPPERONI_tok
%token CHEESE_tok
%token CHOCOLATE_SAUCE_tok
%token PINEAPPLE_tok

%%

lunch : item WITH_tok topping_list PERIOD_tok;

item : PIZZA_tok | SANDWICH_tok | ICE_CREAM_tok ;

topping_list : topping_list AND_tok topping | topping ;

topping : PEPPERONI_tok | CHEESE_tok | CHOCOLATE_SAUCE_tok | PINEAPPLE_tok ;

%%

void yyerror(char* s)
{
   cerr << "parse error on line " << line_num << endl;
   exit(1);
}