n = int(input())
if n == 2 * int(n / 2):
    p = 1 / 2
else:
    p = (n + 1) / (2 * n)
print(p) n = int(input()) n int(input()) int input() input if n == 2 * int(n / 2):
    p = 1 / 2
else:
    p = (n + 1) / (2 * n) n == 2 * int(n / 2) n 2 * int(n / 2) 2 int(n / 2) int n / 2 n 2 p = 1 / 2 p 1 / 2 1 2 p = (n + 1) / (2 * n) p (n + 1) / (2 * n) n + 1 n 1 2 * n 2 n print(p) print p p = 1 / 2 1 / 2 p p = (n + 1) / (2 * n) (n + 1) / (2 * n) p n = int(input()) int(input()) n
n = int(input())
if n == 2 * int(n / 2):
    p = 1 / 2
else:
    p = (n + 1) / (2 * n)
print(p)