#!/usr/bin/perl -w
use strict;
use Benchmark;
my @args = ('ACGTACGTACGT', 2,4,5);

timethese(-2,{
    japhy  => sub{japhy(@args)},
    danger => sub{danger(@args)},
});

@args = ('ACGTACGTACGT' x 4, (2,4,5) x 4);

timethese(-2,{
    japhy  => sub{japhy(@args)},
    danger => sub{danger(@args)},
});

@args = ('ACGTACGTACGT' x 100, (2,4,5) x 100);

timethese(-2,{
    japhy  => sub{japhy(@args)},
    danger => sub{danger(@args)},
});

sub danger {
    my $s = shift;
    join '-', unpack join('A','',@_,'*') ,$s;
}

sub japhy {
    my $s = shift;
    join '-', map(substr($s, 0, $_, ''), @_),$s;
}

__END__

Benchmark: running danger, japhy, each for at least 2 CPU seconds...
    danger:  1 wallclock secs ( 2.06 usr +  0.00 sys =  2.06 CPU) 
             @ 10438.35/s (n=21503)
     japhy:  1 wallclock secs ( 2.06 usr +  0.00 sys =  2.06 CPU) 
             @ 8694.17/s (n=17910)

Benchmark: running danger, japhy, each for at least 2 CPU seconds...
    danger:  2 wallclock secs ( 2.03 usr +  0.00 sys =  2.03 CPU) 
             @ 4800.49/s (n=9745)
     japhy:  3 wallclock secs ( 2.10 usr +  0.00 sys =  2.10 CPU) 
             @ 3409.05/s (n=7159)

Benchmark: running danger, japhy, each for at least 2 CPU seconds...
    danger:  2 wallclock secs ( 2.13 usr +  0.00 sys =  2.13 CPU) 
             @ 258.22/s (n=550)
     japhy:  3 wallclock secs ( 2.01 usr +  0.00 sys =  2.01 CPU) 
             @ 155.72/s (n=313)