N = int(input())
ans = (N - (N//2)) / N
print(ans) N = int(input()) N int(input()) int input() input ans = (N - (N//2)) / N ans (N - (N//2)) / N N - (N//2) N N//2 N 2 N print(ans) print ans ans = (N - (N//2)) / N (N - (N//2)) / N ans N = int(input()) int(input()) N
N = int(input())
ans = (N - (N//2)) / N
print(ans)