X = int(input())
print(((X//2)+1)/X if X % 2 != 0 else 0.5) X = int(input()) X int(input()) int input() input print(((X//2)+1)/X if X % 2 != 0 else 0.5) print ((X//2)+1)/X if X % 2 != 0 else 0.5 X % 2 != 0 X % 2 X 2 0 ((X//2)+1)/X (X//2)+1 X//2 X 2 1 X 0.5 X = int(input()) int(input()) X
X = int(input())
print(((X//2)+1)/X if X % 2 != 0 else 0.5)