%{
#include <stdio.h>
int yyerror (char const *msg) { return 0;}
extern int yylex(); 
#define N 10
%}
%union {  int entier;  char  car; }
%token <car> CHIF
%type  <entier> var
%% 
Axiome : var '\n' {printf("Val=%d\n",$1);}
var : /* vide */  {$$=0;}
    | var CHIF     {$$ = N * $1 + ($2-'0') ;}
%%
int main(void) { return yyparse(); }