Could you post your code to this mailing list or to the wiki at http://haskell.org/hawiki/FannkuchEntry ?
Bertram Felgenhauer wrote: >>And for sanity's sake, I wish one of the entries would have documentated >>a clear way to understand the permutation generator. The PHP and Lua >>versions are almost legible. > > > Here's a neat Haskell version: > > -- rotate initial n elements of the list left by one place > rotate n (x:xs) = rot' n xs where > rot' 1 xs = x:xs > rot' n (x:xs) = x:rot' (n-1) xs > > permutations l = foldr perm' [l] [2..length l] where > perm' n l = l >>= take n . iterate (rotate n) > > Combined with Jan-Willem Maessen's ideas (i.e. the single-pass flop) > this runs about 85 times faster than the current shootout entry. > > Bertram > _______________________________________________ > Haskell-Cafe mailing list > Haskell-Cafe@haskell.org > http://www.haskell.org/mailman/listinfo/haskell-cafe > _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe