Hello monks!

I have the following code :

use strict;
use warnings;
use Tie::File;

my $first   = shift || die "first file\n";
my $sec     = shift || die "second\n";

tie my @first,'Tie::File',$first or die "tie error $!\n";
tie my @sec  ,'Tie::File',$sec or die "tie error $!\n";

my (%h1,%h2,%common);

print "processing $first\n";
map {
  if(/^\s*(\?.*?)\s/) {
    $h1{$1}++;
  }
} @first;

print "processing $sec\n";
map {
  if(/^\s*(\?.*?)\s/) {
    $h2{$1}++;
  }
} @sec;

print "finding common keys\n";
map {
  if(exists $h2{$_}) {
    $common{$_}++;
  }
} keys %h1;

print "there are @{[length keys %common]}:\n";
system("pause");
for my $key(keys %common) {
    print "\n\n\n$key\n\n\n";
}

untie @first;
untie @sec;
[download]

I am using this to find common stuff inside 2 files . My question is :
- if I print length keys %common ,it outputs 3
- if I assign keys %common to an array , it's size is 159 . Why ?

---

In reply to what's wrong with this? by Alien

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