use Modern::Perl;

my %test;
my @predetermined;
my @results;

push @predetermined, int(rand(100)) for 1 .. 100;

for my $element (@predetermined) {
    my $pair;
    {
        $pair = int(rand(100));
        redo if $test{$element.'-'.$pair} or $test{$pair.'-'.$element} or $pair == $element;
    }
    $test{$element.'-'.$pair} = $test{$pair.'-'.$element} = 1;
    push @results, $element.'-'.$pair;
}
say for sort(@results);