use strict;
use warnings;

my %pairs;
my @left = (0,1,2,5,7,8,10); #put your own predetermined numbers

foreach my $val1 (@left){
  my @right = ();
  foreach my $val2 (0..99){
    push(@right, $val2) if $val1 != $val2 && (!exists $pairs{$val2} || $pairs{$val2} != $val1);
  }
  $pairs{$val1} = $right[int(rand($#right+1))];
}

foreach(@left){
  print $_, ',', $pairs{$_}, ' ';
}