my %foo = map( $_ => 2*$_, 1..10 );
use Data::Dumper;
print Dumper(\%foo);

##</code><code>##

$VAR1 = {
          '6' => 12,
          '3' => 6,
          '7' => 14,
          '9' => 18,
          '2' => 4,
          '8' => 16,
          '1' => 2,
          '4' => 8,
          '10' => 20,
          '5' => 10
        };