Factorial

Score: 48.13 (pass)

#!perl -l
$_*=$z%1e9,/0*$/,$z=$`for++$z..pop;print$z%10

Score: 49.10 (pass)

#!perl -l
($z=$_*$z%1e9)=~s|0*$||for++$z..pop;print$z%10