%{
#include <stdio.h>

extern FILE * yyin;

void yyerror(const char * str)
{
    fprintf(stderr, "error: %s\n", str);
}

int yywrap()
{
    return 1;
}

int main(int argc, char * argv[])
{
    if (argc > 0)
    {
        yyin = fopen(argv[1], "r");
    }
    yyparse();
}

%}

%token BIN_NUMBER OCT_NUMBER DEC_NUMBER HEX_NUMBER

%%

program: /* empty */
       | number program { printf("Saw a number\n"); }

number: BIN_NUMBER
      | OCT_NUMBER
      | DEC_NUMBER
      | HEX_NUMBER
      {
        printf("Saw a number\n");
      }
      ;