N = int(input())
if N%2 == 0:
    print(1/2)
else:
    tmp = ((N-1)/2) + 1
    print(tmp/N) N = int(input()) N int(input()) int input() input if N%2 == 0:
    print(1/2)
else:
    tmp = ((N-1)/2) + 1
    print(tmp/N) N%2 == 0 N%2 N 2 0 print(1/2) print 1/2 1 2 tmp = ((N-1)/2) + 1 tmp ((N-1)/2) + 1 (N-1)/2 N-1 N 1 2 1 print(tmp/N) print tmp/N tmp N tmp = ((N-1)/2) + 1 ((N-1)/2) + 1 tmp N = int(input()) int(input()) N
N = int(input())
if N%2 == 0:
    print(1/2)
else:
    tmp = ((N-1)/2) + 1
    print(tmp/N)
