for ($i = 0; $i < 10; $i++) {
   $hash{2823}[$i] = "2823_$i.xml";
}
 
foreach $key (keys %hash) {
   foreach $xml (0..$#{$hash{$key}}) {
      print "Key: $key/$xml => " . $hash{$key}[$xml] . "\n";
   }
}


Key: 2823/0 => 2823_0.xml
Key: 2823/1 => 2823_1.xml
Key: 2823/2 => 2823_2.xml
Key: 2823/3 => 2823_3.xml
Key: 2823/4 => 2823_4.xml
Key: 2823/5 => 2823_5.xml
Key: 2823/6 => 2823_6.xml
Key: 2823/7 => 2823_7.xml
Key: 2823/8 => 2823_8.xml
Key: 2823/9 => 2823_9.xml