Like this. 
my %count;
while(<DATA>) {
    chomp;
    tr/,/\t/;
    $count{$_}++;
}
foreach(sort keys %count) {
    print "$count{$_}\t$_\n";
}

__DATA__
abcd,US
abee,UK
abcd,US
adee,US

[download]
Replace <DATA> with "<>" to run it for real, and either pipe in the data file or pass the filename as an argument to the script.

In reply to Re: Dear Monks by bart
in thread Dear Monks by sivaraman

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


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