To help you on your way, here's a recursive solution for merge sort: 
    sub merge {
        my ($f, $s, @r) = @_;
        push @r => shift @{$$f [0] < $$s [0] ? $f : $s} while @$f && @
+$s;
       (@r, @$f, @$s);
    }
    sub merge_sort;
    sub merge_sort {
        @_ <= 1 ? @_ : merge [merge_sort @_ [0 .. @_ / 2 - 1]],
                             [merge_sort @_ [@_ / 2 .. $#_]]
    }

[download]

The recursive solution is elegant, and just 10 lines. I don't really want to think about the iterative solution.

Abigail

In reply to Re: Recursion Alternatives? by Abigail-II
in thread Recursion Alternatives? by Cabrion

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