in reply to Need help on hashes.

Although you say that you put the values on a hash, you don't. The code you show us puts them onto an array. 
my %countries;
while (<DB>){
    my @entries = split m/,/, $_;
    $countries{$entries[1]}++;
}

for (reverse sort { $countries{$a} <=> $countries{$b} } keys %countrie
+s){
    print "$_\t\$countries{$_}\n";
}

[download]
should do the trick (untested).

Update: no, the \ was not intentional, of course it's print "$_\t$countries{$_}\n";. Thanks cdarke.

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Re^2: Need help on hashes.
by cdarke (Prior) on Feb 04, 2008 at 09:08 UTC
    Is the \ in front of the $ in the print statement intentional? That gives:
    "US"    $countries{"US"}
"DE"    $countries{"DE"}
"RU"    $countries{"RU"}
"UK"    $countries{"UK"}
"FR"    $countries{"FR"}

    [download]
    Also it retains the quotes around the country code. I have:
    my %countries;
while (<DB>){
    my $entry = (split /","/, $_)[1];
    $countries{$entry}++;
}

for (reverse sort { $countries{$a} <=> $countries{$b} } keys %countrie
+s){
    print "$_\t$countries{$_}\n";
}

    [download]
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[d/l]
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      Thank you all for the responses. The example and the explanation are very informative. Hopefully, I'll not experience (i.e. create) any errors when try it out in my script. :-)

      For the record, this is not a homework assignment as apl implies. It's a reasonable thing to suspect but it's incorrect and I don't want the monks to think I'm taking advantage of their help. I'm a network engineer tasked with making sense out of years worth of accumulated syslog data. My code skills (a little C 10 years ago and sporadic uses of perl over the years) are quite limited. The question about whether or not to use a hash was a sincere inquiry as I wasn't sure if there was a more appropriate structure which to employ.

      Thank you all again for your help. It is sincerely appreciated.

      Rob
      ElMagnifico - Ask for it in your grocer's freezer.
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