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