maze traversal I need help.

[SGb4jE8b]

01	#include <stdio.h>
02	 
03	#define FALSE 0
04	#define TRUE 1
05	 
06	#define NROWS 6
07	#define MCOLS 6
08	 
09	// Symbols:
10	// '.' = open
11	// '#' = blocked
12	// 'S' = start
13	// 'G' = goal
14	// '+' = path
15	// 'x' = bad path
16	char maze[NROWS][MCOLS] = {
17	    "S...##",
18	    "#.#...",
19	    "#.##.#",
20	    "..#.##",
21	    "#...#G",
22	    "#.#..."
23	};
24	 
25	 
26	void display_maze(void);
27	int find_path(int x, int y);
28	 
29	 
30	int
31	main(void)
32	{
33	    display_maze();
34	 
35	    if ( find_path(0, 0) == TRUE )
36	        printf("Success!\n");
37	    else
38	        printf("Failed\n");
39	 
40	    display_maze();
41	 
42	    return 0;
43	}
44	// main()
45	 
46	 
47	void
48	display_maze(void)
49	{
50	    int i;
51	 
52	    printf("MAZE:\n");
53	    for ( i = 0; i < NROWS; i++ )
54	        printf("%.*s\n", MCOLS, maze[i]);
55	    printf("\n");
56	 
57	    return;
58	}
59	 
60	 
61	int
62	find_path(int x, int y)
63	{
64	    // If x,y is outside maze, return false.
65	    if ( x < 0 || x > MCOLS - 1 || y < 0 || y > NROWS - 1 ) return FALSE;
66	 
67	    // If x,y is the goal, return true.
68	    if ( maze[y][x] == 'G' ) return TRUE;
69	 
70	    // If x,y is not open, return false.
71	    if ( maze[y][x] != '.' && maze[y][x] != 'S' ) return FALSE;
72	 
73	    // Mark x,y part of solution path.
74	    maze[y][x] = '+';
75	 
76	    // If find_path North of x,y is true, return true.
77	    if ( find_path(x, y - 1) == TRUE ) return TRUE;
78	 
79	    // If find_path East of x,y is true, return true.
80	    if ( find_path(x + 1, y) == TRUE ) return TRUE;
81	 
82	    // If find_path South of x,y is true, return true.
83	    if ( find_path(x, y + 1) == TRUE ) return TRUE;
84	 
85	    // If find_path West of x,y is true, return true.
86	    if ( find_path(x - 1, y) == TRUE ) return TRUE;
87	 
88	    // Unmark x,y as part of solution path.
89	    maze[y][x] = 'x';
90	 
91	    return FALSE;
92	}
93	// find_path() 

the algorithm is from this site http://www.cs.bu.edu/teaching/alg/maze/

I want to understand the algorithms of the maze traversal and generation of mazes. Please guys.

[steve9164]

What is your question?

[viliml]

This isn't C++.

[Peter87]

Strings are null terminated (the last char is '\0') so the strings used to initialize maze is of length 7 but MCOLS is only 6. If you want to use string literals to initialize the maze you will have to make the maze one bigger.

char maze[NROWS][MCOLS + 1] = {
	"S...##",
	"#.#...",
	"#.##.#",
	"..#.##",
	"#...#G",
	"#.#..."
};

[viliml]

It's actually REALLY easy. I done this in 15 minutes. I'm not gonna give you the solution if you want to keep trying, buf if you give up, just say the word!

[Peter87]

viliml wrote:

It's actually REALLY easy.

Everything is easy if you know how to do it.

[viliml]

True... So I might as well say "I actually REALLY know how to do it.":D Seriously though, the only thing I see at first sight in that code that's wrong is that it's not C++, but pure C, if not worse...

[Peter87]

The code is valid C code and valid C++ code.

[viliml]

OK,you want me to post my soslution?

[SGb4jE8b]

i need your help guys. i don't know how to write the maze traversing application i need some pseudo-code or anything that will help me understand how to do it my self. the code is not mine, i need to do mine.