my %vals=( 1 => '0', 2 => '3', 3 => '5');
my @arr = ( 0,1,2,3,4,5,6 );

my @res;
for my $key ( sort{ $a <=> $b } keys %vals ){
  push @res, $arr[$vals{ $key }];
}

print join (',', @res );

##</code><code>##

print join (',', @arr[@res] );

##</code><code>##

  push @res, $vals{ $key };