$string = "atccatccctttaat";
$triplets0 = $line=~ /(...)/;

##</code><code>##

$string = "atccatccctttaat";
($triplets0) = $line=~ /(...)/;

##</code><code>##

$string = "atccatccctttaat";
@triplets0 = $line=~ /(...)/;