/* http://www.linux-france.org/article/devl/lexyacc/minimanlexyacc-4.html */
%{

  /*#include "global.h"*/
#define YYSTYPE double

#include <stdio.h>
#include <stdlib.h>
#include <math.h>

%}

%token  NUM
%token  PLUS MINUS TIMES  DIV
%token  LPAR RPAR
%token  NL

%left PLUS MINUS
%left TIMES DIV
%left NEG

%start input
%%

input:
    /* Vide */
  | input line
  ;

line:
    NL        { printf("Resultat :\n"); }
  | exp NL    { printf("Resultat : %f\n",$1); }
  ;

exp:
    NUM                  { printf("num: %f\n",$1); $$ = $1; }
  | exp PLUS exp         { $$ = $1 + $3; }
  | exp MINUS exp        { $$ = $1 - $3; }
  | exp TIMES exp        { $$ = $1 * $3; }
  | exp DIV exp          { $$ = $1 / $3; }
  | MINUS exp %prec NEG  { $$ = -$2; }
  | LPAR exp RPAR        { $$ = $2; }
  ;

%%

int yyerror(char *s) {
  printf("error: %s\n",s);
  return 1;
}

int main(void) {
  yyparse();
  return 0;
}