n = int(input())

if n%2 == 0:
  print(float((n//2)/n))
elif n == 1:
  print(float(1))
else:
  print(float((n//2 + 1)/n)) n = int(input()) n int(input()) int input() input if n%2 == 0:
  print(float((n//2)/n))
elif n == 1:
  print(float(1))
else:
  print(float((n//2 + 1)/n)) n%2 == 0 n%2 n 2 0 print(float((n//2)/n)) print float((n//2)/n) float (n//2)/n n//2 n 2 n elif n == 1:
  print(float(1)) n == 1 n 1 print(float(1)) print float(1) float 1 print(float((n//2 + 1)/n)) print float((n//2 + 1)/n) float (n//2 + 1)/n n//2 + 1 n//2 n 2 1 n n = int(input()) int(input()) n
n = int(input())

if n%2 == 0:
  print(float((n//2)/n))
elif n == 1:
  print(float(1))
else:
  print(float((n//2 + 1)/n))