in reply to using hashes to count

To continue from where mortiz left off, summing up the values is easy too. 
my %rh_count;
$rh_count{$string} += $value;

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Re^2: using hashes to count
by spiros (Beadle) on Jun 14, 2007 at 23:01 UTC
    Thank you both of your replies. Yes i am just counting up the occurrences of the strings. What i am worried is, without the 'exists' check, $rh_count->{$keyword}++ would give a warning since it would be undef (provided that it wouldnt have been used before)
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      Usual way:

      my @strings = qw/ a a b c a b c d e a b c a b c d /;

my %count;
foreach ( @strings ) {
  $count{$_} ||= 0;
  $count{$_}++;
}

# Then, if you want to sort the results by value:

foreach ( sort { $count{$a} <=> $count{$b} } keys %count ) {
  print "$_ => $count{$_}\n";
}

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[d/l]
        The $count{$_} ||= 0; is useless. ++ doesn't give undefined warnings.
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        Excellent, thank you very much.
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