Factorial

Score: 53.16 (pass)

#!perl -l
$_*=$a,/0*$/,$a=$`%10**9for($a=1)..pop;print$a%10;

Score: 54.16 (pass)

#!perl -l
$a=1;$_*=$a,/0*$/,$a=$`%10**9for 1..pop;print$a%10;