Say we pass a function two variables, both are strings. We want to return true or false depending on whether we can form the string in the second argument from the letters in the string in the first argument. Here's my working version. My question is what is the best way to do this with efficiency being of utmost importance? (since i do this about a million times). Is there a faster regex that could do this better than my logic algorithm? or can someone think of a better logical solution altogether? thanks a lot for your help. 
#This bool function returns whether the second argument
#string can be built with the first arguments letters
sub match($$$) {
    my ($self,$letters,$word) = @_;
    $letters = lc($letters);
    $word = lc($word);


    #Now we build our hashes
    my (%letter_hash, %word_hash);
    while($letters) {
        $letter_hash{chop($letters)}++;
    }
    while($word) {
        $word_hash{chop($word)}++;
    }


    #Now to analyze
    my ($key, $value);
    while(($key,$value) = each(%word_hash)) {
        $letter_hash{$key} = $letter_hash{$key} - $value;
        return 0 if ($letter_hash{$key} < 0);
    }


    #Must be good
    return 1;
}

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In reply to Finding One String in Another by Fideist11

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