On Wed, 9 Nov 2005, Sybren Stuvel wrote: > Ian Vincent enlightened us with: > >> I have never used generators before but I might have now found a use >> for them. I have written a recursive function to solve a 640x640 maze >> but it crashes, due to exceeding the stack. The only way around this I >> can think of is to use Generator but I have no idea how to. > > A better way is to use a queue. I had the same problem with a similar > piece of code. The only thing why you're using a stack is to move to > the "next" point, without going back to a visited point.
Exactly - using a queue means you'll do a breadth-first rather than a depth-first search, which will involve much less depth of recursion. See: http://cs.colgate.edu/faculty/nevison.pub/web102/web102S00/Notes12.htm For details. An extended version of this exercise would be to implement an A* search: http://en.wikipedia.org/wiki/A-star_search_algorithm Which might be quicker than a blind breadth-first. tom -- Exceptions say, there was a problem. Someone must deal with it. If you won't deal with it, I'll find someone who will. -- http://mail.python.org/mailman/listinfo/python-list