def main():
  num = int(input())
  print(1-((int(num/2)/num)))
main() def main():
  num = int(input())
  print(1-((int(num/2)/num))) main num = int(input()) num int(input()) int input() input print(1-((int(num/2)/num))) print 1-((int(num/2)/num)) 1 int(num/2)/num int(num/2) int num/2 num 2 num main() main def main():
  num = int(input())
  print(1-((int(num/2)/num))) def main():
  num = int(input())
  print(1-((int(num/2)/num))) main
def main():
  num = int(input())
  print(1-((int(num/2)/num)))
main()