d=1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586878889909192939495969798991
n=gets.to_i
if n<=8
  print "0.",d*n,"\n"
elsif
  ans = (d*n).to_s
  print ans[0,ans.length-190],".",ans[-190,10000],"\n"
end