my %hash = map { my($k,$v)=split/#/; $k=int($k); ($k,$v) } @array2;

for (@array1) {
   my $k = int($_);
   next if !exists($hash{$k});
   print("$hash{$k} = $_\n");
}

##</code><code>##

my %hash;
for (@array2) {
   my ($k, $v) = split /#/;
   $k = int($k);
   push @{ $hash{$k} }, $v;
}

for (@array1) {
   my $k = int($_);
   next if !exists($hash{$k});
   for my $v (@{ $hash{$k} }) {
      print("$v = $_\n");
   }
}