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sub fact{ (map{$_[0]*=$_}1..$_[0]-1)[-1]||1 # 33 ... }
perl -e "sub fact{$x=$_;$x<0?'E':(map{$x*=$_}1..$x-1)[-1]||1} print ma +p{fact($_),qq(\n)}@ARGV " 0 1 3 -1 ... 6 E