// maze constants and datatypes
//
// R. Perry, March 1991; updated Nov 2006, Jan 2016, Apr 2023
//
extern int debug, solve;

/* left, down wall values */

#define OPEN   0
#define CLOSED 1

/* cell types */

#define SPANTREE 0
#define FRONTIER 1
#define NEITHER  2

/* solution path flags */

#define OFF  0
#define ON   1 /* 001 */
#define LEFT 2 /* 010 */
#define DOWN 4 /* 100 */

struct cell
{
  unsigned int left:1, down:1, type:2;
  unsigned int path:3; /* solution path flag */
};

/* frontier stack cell */

struct frontier
{
  int row, col;
};

typedef void (*Maze_fn)( struct cell **maze, int m, int n);

int irand( int n);
void shuffle( int a[], int n);
struct cell **maze_alloc( int m, int n);
void maze_init( struct cell **maze, int m, int n);
int maze_read( struct cell **maze, int m, int n);
void maze_print_raw( struct cell **maze, int m, int n);
void maze_print_X( struct cell **maze, int m, int n);