N = int(input())

if 2 <= N and N%2 == 0:
    print(((N//2)/N))

elif 2<=N and N%2 != 0:
    print(((N+1)//2)/N)

else:
    print("1.00000") N = int(input()) N int(input()) int input() input if 2 <= N and N%2 == 0:
    print(((N//2)/N))

elif 2<=N and N%2 != 0:
    print(((N+1)//2)/N)

else:
    print("1.00000") 2 <= N and N%2 == 0 2 <= N 2 N N%2 == 0 N%2 N 2 0 print(((N//2)/N)) print (N//2)/N N//2 N 2 N elif 2<=N and N%2 != 0:
    print(((N+1)//2)/N) 2<=N and N%2 != 0 2<=N 2 N N%2 != 0 N%2 N 2 0 print(((N+1)//2)/N) print ((N+1)//2)/N (N+1)//2 N+1 N 1 2 N print("1.00000") print "1.00000" N = int(input()) int(input()) N
N = int(input())

if 2 <= N and N%2 == 0:
    print(((N//2)/N))

elif 2<=N and N%2 != 0:
    print(((N+1)//2)/N)

else:
    print("1.00000")