Are your lists big? And do you really need the best solution, or is a good approximation sufficient?

I think that Dominus' book Higher Order Perl contains an example for something similar, and if I remember correctly it just went through all possible solutions, which doesn't scale very well for long lists.

Update: Here's a very simple approximative solution (after finding out that it might be good enough): 

#!/usr/bin/perl
use strict;
use warnings;
use List::Util qw(sum);

divide(8,14,32,29);
divide(7,10,12,15,40);

sub divide {
    my @array = reverse sort { $a <=> $b} @_;
    my $target = sum(@array) / 2;

    my @result;
    my $current = 0;

    for (@array) {
        if ($current + $_ <= $target) {
            push @result, $_;
            $current += $_;
        }
    }
    print "@result\n";
    print "Target: $target; Result: $current\n";
}
__END__
 32
Target: 41.5; Result: 40
7 15 12
Target: 42; Result: 34

[download]

If that's not good enough you can iterate over all pairs of values from distinct sets and see if the reached value improves. If it does, swap these two elements.

(second update: fixed sort. FunkyMonk++)

In reply to Re: Divide array of integers into most similar value halves by moritz
in thread Divide array of integers into most similar value halves by Pepe

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