/*
 * For concreteness/ease of understanding,
 * we assume throughout that an int is 32-bits,
 * though the code that uses BITS_PER_WORD is
 * still available.
 */
#define	BITS_PER_WORD	32
#define	SYMBOLIC	1

extern int	width, height;

unsigned int	grid_words(int  width,
			   int	height);
int	cell_alive(unsigned int	*grid,
		   int		r,
		   int		c);
void	set_cell(unsigned int	*grid,
		 int		r,
		 int		c,
		 int		status);
void	life_xform(unsigned int	*grid,
		   unsigned int	*grid2);