N = int(input())

num = (N+1)//2

print(num/N) N = int(input()) N int(input()) int input() input num = (N+1)//2 num (N+1)//2 N+1 N 1 2 print(num/N) print num/N num N N = int(input()) int(input()) N num = (N+1)//2 (N+1)//2 num
N = int(input())

num = (N+1)//2

print(num/N)
