def odd(num):
	return num//2+num%2

N=int(input())

num = odd(N)/N
print("{:.10f}".format(num)) def odd(num):
	return num//2+num%2 odd return num//2+num%2 num//2+num%2 num//2 num 2 num%2 num 2 num num N=int(input()) N int(input()) int input() input num = odd(N)/N num odd(N)/N odd(N) odd N N print("{:.10f}".format(num)) print "{:.10f}".format(num) "{:.10f}".format "{:.10f}" format num N=int(input()) int(input()) N def odd(num):
	return num//2+num%2 def odd(num):
	return num//2+num%2 odd num = odd(N)/N odd(N)/N num
def odd(num):
	return num//2+num%2

N=int(input())

num = odd(N)/N
print("{:.10f}".format(num))