Factorial

Score: 66.11 (pass)

#!perl -l
map{until($_%5){$_/=5;$p/=2}$p=$p%10**5*$_}++$p..pop;print$p%10

Score: 73.12 (pass)

#!perl -l
$_=1;for$f(1..pop){until($f%5){$f/=5;$_/=2}$_=($_%10**5)*$f}print$_%10