#!ruby -n
d=->n{n<10?n: d[n/10+n%10]}
f=->n,k=1{(k..n).reduce(:*)||1}
l=(~/$/)
p d(l.times.reduce(0){|m,i|m+$_[i].hex*f[l-1,l-i]/f[i]})if$.>1