#include <stdio.h>

#define FALSE 0
#define TRUE 1

#define NROWS 6
#define MCOLS 6

// Symbols:
// '.' = open
// '#' = blocked
// 'S' = start
// 'G' = goal
// '+' = path
// 'x' = bad path
char maze[NROWS][MCOLS] = {
   "S...##",
   "#.#...",
   "#.##.#",
   "..#.##",
   "#...#G",
   "#.#..."
};


void display_maze(void);
int find_path(int x, int y);


int
main(void)
{
   display_maze();

   if ( find_path(0, 0) == TRUE )
       printf("Success!\n");
   else
       printf("Failed\n");

   display_maze();

   return 0;
}
// main()


void
display_maze(void)
{
   int i;

   printf("MAZE:\n");
   for ( i = 0; i < NROWS; i++ )
       printf("%.*s\n", MCOLS, maze[i]);
   printf("\n");

   return;
}


int
find_path(int x, int y)
{
   // If x,y is outside maze, return false.
   if ( x < 0 || x > MCOLS - 1 || y < 0 || y > NROWS - 1 ) return FALSE;

   // If x,y is the goal, return true.
   if ( maze[y][x] == 'G' ) return TRUE;

   // If x,y is not open, return false.
   if ( maze[y][x] != '.' && maze[y][x] != 'S' ) return FALSE;

   // Mark x,y part of solution path.
   maze[y][x] = '+';

   // If find_path North of x,y is true, return true.
   if ( find_path(x, y - 1) == TRUE ) return TRUE;

   // If find_path East of x,y is true, return true.
   if ( find_path(x + 1, y) == TRUE ) return TRUE;

   // If find_path South of x,y is true, return true.
   if ( find_path(x, y + 1) == TRUE ) return TRUE;

   // If find_path West of x,y is true, return true.
   if ( find_path(x - 1, y) == TRUE ) return TRUE;

   // Unmark x,y as part of solution path.
   maze[y][x] = 'x';

   return FALSE;
}
// find_path()

char maze[NROWS][MCOLS] = {
   "S...##",
   "#.#...",
   "#.##.#",
   "..#.##",
   "#...#G",
   "#.#..."
};

char maze[NROWS][MCOLS] = {
  "S...##",
  "#.#...",
  "#.##.#",
  "..#.##",
  "#...#G",
  "#.#..."
};