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