dijkstra longest path

ch3.py

@@ -1,18 +1,7 @@
-import grid
-import binary
-import sidewinder
-import pretty
 import dijkstra
+import sidewinder
 
 dg = dijkstra.DijkstraGrid(6, 7)
 b = sidewinder.SideWinder(dg)
-dg.build_distances(dg.grid[0][0])
-dg.path_to(dg.grid[5][0])
-
+dg.set_longest_path()
 print(dg)
-#print(d.distances)
-#p = pretty.Pretty(g)
-
-
-
-

dijkstra.py

@@ -46,6 +46,18 @@ def path_to(self, t):
         self.last_path = path
         return path
 
+    # sets last_path to longest path
+    def set_longest_path(self):
+
+        # a longest path starts at the furtherest cell from (0,0)
+        self.build_distances(self.grid[0][0])
+        origin = max(self.distances, key=self.distances.get)
+
+        self.build_distances(origin)
+        dest = max(self.distances, key=self.distances.get)
+
+        self.path_to(dest)
+