Hi all I'm looking for a fast way of converting a sequence of four characters (a,b,c,d) to a number. So far I use 

my $lt = [];
$lt->[ord(a)] = 00;
$lt->[ord(b)] = 01;
$lt->[ord(c)] = 10;
$lt->[ord(d)] = 11;

foreach my $string{
_convert($string);

...
sub _convert{
my $string = shift;
my $bs="";
foreach(split(//,$string)){

$bs.=$lt->[$_];
}

return int($bs);
}

[download]
I also tried using a hash of form {a=>00,b=>01,c=>10,d=>11} or use four substitutes on $string which should have been kind of four times the runtime (processing the complete string 4 times). But somehow the regexp substitution seems to be the fastest. However, it's still pretty slow if I'm iterating over millions of strings. Any faster solution? Cheers, Lowry

In reply to convert each character of a string to number by Lowry76

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