a working non-recursive floodfill algorithm written in C?

Question

I\'ve been trying to find a working floodfill algorithm. Of the many algorithms I\'ve tried only the \'recursive line fill\' one behaves exactly as it should with the major

Answer 1

I have a non-recursive flood fill, but I won't post it because it's the solution to a homework assignment. But here's a hint: depth-first search, which is the natural algorithm, uses far more auxiliary space than a breadth-first search. Here's what I wrote at the time (suitably expurgated):

I dare not try depth-first search by simple recursion; the depth of recursion is limited only by REDACTED, and my experiments show that an PROBLEM REDACTED could nevertheless require a stack depth of over a million. So I put the stack in an auxiliary data structure. Using an explicit stack actually makes it easy to try breadth-first search as well, and it turns out that breadth-first search can use forty times less space than depth-first search.

For my data structure I used the Seq_T from Dave Hanson's C Interfaces and Implementations; changing from depth-first to breadth-first requires changing just one function call.