open(IN, 'in.txt') || die $!;
open(OUT, '>', 'out.txt') || die $!;
while(<IN>)
{
  chomp;
  print OUT substr($1, 3) . ";\n" foreach(/(\d{10})/g)
}
close IN;
close OUT;

Entries are returned in an apparently random order. The actual
random order is subject to change in future versions of perl,
but it is guaranteed to be in the same order as either the
"keys" or "values" function would produce on the same
(unmodified) hash. Since Perl 5.8.1 the ordering is different
even between different runs of Perl for security reasons (see
"Algorithmic Complexity Attacks" in perlsec).

%hash =('1'=>'1',
'2'=>'2',
'3'=>'3');

foreach $k (sort keys %hash){
print "$k => $hash{$k} \n";
}