import algorithm, sequtils, strutils

const
  D = "0.1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586878889909192939495969798991"


let
  n = parseInt stdin.readLine
var
  list: seq[string]
  tmp = 0

for c in D.toSeq.reversed:
  if c == '.':
    list.add "."
    continue
  var
    x = ($c).parseInt
  x = x * n + tmp
  tmp = x div 10
  list.add $(x mod 10)

if tmp != 0:
  list.add $tmp

echo list.reversed.join