def solve(N):

    odd_count = 0



    for x in range(1, N + 1)[::-1]:

        if x % 2 == 1:

            odd_count += 1



    if N == 1:

        return 1



    return odd_count / N





N = int(eval(input()))



print((solve(N)))

def filter_odd(x):

    return x % 2 == 1





def solve(N):

    odd_list = list(

        filter(filter_odd, list(range(1, N + 1))[::-1])

    )

    return len(odd_list) / N





N = int(eval(input()))



print((solve(N)))

def solve(N):
    odd_count = 0
    for x in range(1, N + 1)[::-1]:
        if x % 2 == 1:
            odd_count += 1
    if N == 1:
        return 1
    return odd_count / N


N = int(eval(input()))
print((solve(N)))

def filter_odd(x):
    return x % 2 == 1


def solve(N):
    odd_list = list(filter(filter_odd, list(range(1, N + 1))[::-1]))
    return len(odd_list) / N


N = int(eval(input()))
print((solve(N)))

+def filter_odd(x): +    return x % 2 == 1 + + -    odd_count = 0 -    for x in range(1, N + 1)[::-1]: -        if x % 2 == 1: -            odd_count += 1 -    if N == 1: -        return 1 -    return odd_count / N +    odd_list = list(filter(filter_odd, list(range(1, N + 1))[::-1])) +    return len(odd_list) / N