Pardon me? That example would presumably return a sorting network or certain size and type; I'm not sure what you mean by "sort two networks". Memoization helps there because of recursive structure. I'll give another example that requires no explanation.

sub fibonacci {
  my $n = shift;
  return 0+($n==1) if $n < 2;

  state @mem;

  $mem[$n] //= fibonacci($n-1) + fibonacci($n-2);
}
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Sorry, I didn't know about sorting networks.

There are different kinds of Fibonacci sequences, and some of them are used in practice, e.g. in polyphase merge sort. You need to clear the cache when the number of runs or number of files changes.

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
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