linus sellberg wrote:
> #traverse backwards from the end node
>   path = [end_node]
>   path.inject([]){|acc,node|
>     unless node == start_node
>       path <<  board[node[0]][node[1]]
>       acc  << node
>     end
>   }


I wonder what I thought here, this should be an #each instead, I never 
use the accumulated value :)