A Long Tail

Meet Ralph and Rex

Rex: an experienced dog that has been around the block a time or two

Ralph: a young dog who hasn’t learned to use his deductive skills yet

Enter               

                 

                 

                 

                 

                 

                 

                 

               Exit

Ralph and Rex will both enter this room in an attempt to find the exit. There are three locations (entrance, 2, 3) that will require Ralph and Rex to make a decision about which direction to turn. Notice that the exit is unreachable.

3

2

Enter               

                 

                 

                 

                 

                 

                 

                 

               Exit

Enter               

                 

                 

                 

                 

                 

                 

                 

               Exit

Ralph and Rex both both enter the room in search of the exit. They have each tried the same path moving east, then south, then east again and have found that it has led them to loop back on themselves. A little discouraged, they both return to location 3.

Enter               

                 

                 

                 

                 

                 

                 

                 

               Exit

Ralph and Rex both try moving to the west instead of east this time. Ralph continues along the path until he finds himself at another dead end. Rex has developed a very keen sense of smell and remembers that he has already crossed the path to the west. He knows that moving west will not help him find the exit.

Enter               

                 

                 

                 

                 

                 

                 

                 

               Exit

Enter               

                 

                 

                 

                 

                 

                 

                 

               Exit

After checking both paths available at location 3, Ralph and Rex return to location 2 to try the west path. Rex does not smell that he has crossed this path before, so he chooses to move forward. Again finding themselves at dead ends, Ralph and Rex move back to the entrance.

Enter               

                 

                 

                 

                 

                 

                 

                 

               Exit

Enter               

                 

                 

                 

                 

                 

                 

                 

               Exit

Ralph and Rex determine to move south from the entrance. Ralph continues along his path until he finds himself at another dead end. Meanwhile, Rex senses that he has already been south and has no other path that he can take. He concludes that there is no path to the exit and leaves to find a bowl of food.

Enter               

                 

                 

                 

                 

                 

                 

                 

               Exit

Enter               

                 

                 

                 

                 

                 

                 

                 

               Exit

Ralph still has a few more paths to traverse before he is sure that there is no possible path to the exit. Finally, he concludes that the exit is unreachable and leaves much more tired than he ever expected to find Rex and that bowl of food.

Enter               

                 

                 

                 

                 

                 

                 

                 

               Exit