n = int(input())

if n == 1:
  print(1)
elif n % 2 == 0:
  print(0.5)
else:
  import math
  print(math.ceil(n/2)/n) n = int(input()) n int(input()) int input() input if n == 1:
  print(1)
elif n % 2 == 0:
  print(0.5)
else:
  import math
  print(math.ceil(n/2)/n) n == 1 n 1 print(1) print 1 elif n % 2 == 0:
  print(0.5) n % 2 == 0 n % 2 n 2 0 print(0.5) print 0.5 import math math print(math.ceil(n/2)/n) print math.ceil(n/2)/n math.ceil(n/2) math.ceil math ceil n/2 n 2 n n = int(input()) int(input()) n
n = int(input())

if n == 1:
  print(1)
elif n % 2 == 0:
  print(0.5)
else:
  import math
  print(math.ceil(n/2)/n)