From 52801d8ad7f46b355c3424ee785c5455dc7ba0bc Mon Sep 17 00:00:00 2001
From: Stephen McQuay <stephen@mcquay.me>
Date: Wed, 31 Oct 2012 21:36:52 -0700
Subject: [PATCH] fixed solving of maze

---
 maze/__init__.py | 68 +++++++++++++++++++++++-------------------------
 1 file changed, 32 insertions(+), 36 deletions(-)

diff --git a/maze/__init__.py b/maze/__init__.py
index fbafcdf..434fc32 100644
--- a/maze/__init__.py
+++ b/maze/__init__.py
@@ -1,54 +1,50 @@
 import copy
 from random import randint
 
+WALL = 0
+EMPTY = 1
+PATH = 2
+TEMP = 3
+
 
 class CS235Maze(object):
     def __init__(self, data):
         self._data = data
         self._size = len(data)
 
-    def _solve(self, x, y, z, visited):
-        print x, y, z
-        if all(i == self._size - 1 for i in (x, y, z)):
+    def _solve(self, x, y, z):
+        if x < 0 or y < 0 or z < 0 or \
+                x >= self._size or y >= self._size or z >= self._size:
+            return False
+        elif self._data[x][y][z] != EMPTY:
+            return False
+        elif x == self._size - 1 and y == self._size - 1 \
+                                            and z == self._size - 1:
+            self._data[x][y][z] = PATH
             return True
-
-        if x - 1 >= 0 and (x - 1, y, z) not in visited:
-            _v = copy.deepcopy(visited)
-            _v.add((x - 1, y, z))
-            return self._solve(x - 1, y, z, _v)
-        if x + 1 < self._size and self._data[x + 1][y][z] and (x + 1, y, z) not in visited:
-            _v = copy.deepcopy(visited)
-            _v.add((x + 1, y, z))
-            return self._solve(x + 1, y, z, _v)
-
-        if y - 1 >= 0 and (x, y - 1, z) not in visited:
-            _v = copy.deepcopy(visited)
-            _v.add((x, y - 1, z))
-            self._solve(x, y - 1, z, _v)
-        if y + 1 < self._size and self._data[x][y + 1][z] and (x, y + 1, z) not in visited:
-            _v = copy.deepcopy(visited)
-            _v.add((x, y + 1, z))
-            return self._solve(x, y + 1, z, _v)
-
-        if z - 1 >= 0 and (x, y, z - 1) not in visited:
-            _v = copy.deepcopy(visited)
-            _v.add((x, y, z - 1))
-            return self._solve(x, y, z - 1, _v)
-        if z + 1 < self._size and self._data[x][y][z + 1] and (x, y, z + 1) not in visited:
-            _v = copy.deepcopy(visited)
-            _v.add((x, y, z + 1))
-            return self._solve(x, y, z + 1, _v)
+        else:
+            self._data[x][y][z] = PATH
+            if self._solve(x - 1, y, z) or \
+                    self._solve(x + 1, y, z) or \
+                    self._solve(x, y - 1, z) or \
+                    self._solve(x, y + 1, z) or \
+                    self._solve(x, y, z - 1) or \
+                    self._solve(x, y, z + 1):
+                return True
+            else:
+                self._data[x][y][z] = TEMP
+                return False
 
 
     def solve(self):
-        return self._solve(0, 0, 0, set())
+        return self._solve(0, 0, 0)
 
     def __str__(self):
-        r = derp_transpose(self.data)
+        r = derp_transpose(self._data)
         rs = ''
-        for i in xrange(self.size):
-            for j in xrange(self.size):
-                for k in xrange(self.size):
+        for i in xrange(self._size):
+            for j in xrange(self._size):
+                for k in xrange(self._size):
                     rs += '{} '.format(r[i][j][k])
                 rs += '\n'
             rs += '\n'
@@ -63,7 +59,7 @@ def make_maze(size=8):
             r[i].append([randint(0, 1) for k in xrange(size)])
     r[0][0][0] = 1
     r[size - 1][size - 1][size - 1] = 1
-    return CS235Maze(r, size)
+    return CS235Maze(r)
 
 
 def parse_maze(maze):