use strict;

my @list = (-25, 14, 50, 20, -7, -8, -10);
my @result = (); 
my $sum;
for my $elem (@list) {
    for (@{[@result]}) {
        push @result, [ @$_, $elem ];
        $sum = eval join '+' => @{$result[-1]};
        print join(',', @{$result[-1]}), "\n" unless $sum; 
    }
    push @result, [ $elem ];
    print $elem, "\n" unless $elem;
}