Select Code to Download

use warnings;
use strict;
...
sub do_regex {
    return $str =~ /(?=(...))/g;
}

Jus ust st  t A  An Ano not oth the her er  r P  Pe Per erl rl  l H  H
+a Hac ack cke ker 
Jus ust st  t A  An Ano not oth the her er  r P  Pe Per erl rl  l H  H
+a Hac ack cke ker 
...
substr   25123/s     --   -48%   -97%
mapstr   48651/s    94%     --   -95%
regex  1003705/s  3895%  1963%     --