N = int(input())

if N == 1:
  print(1)
elif N % 2 == 0:
  print(0.5)
else:
  print(-(-N//2) / N) N = int(input()) N int(input()) int input() input if N == 1:
  print(1)
elif N % 2 == 0:
  print(0.5)
else:
  print(-(-N//2) / N) N == 1 N 1 print(1) print 1 elif N % 2 == 0:
  print(0.5) N % 2 == 0 N % 2 N 2 0 print(0.5) print 0.5 print(-(-N//2) / N) print -(-N//2) / N -(-N//2) -N//2 -N N 2 N N = int(input()) int(input()) N
N = int(input())

if N == 1:
  print(1)
elif N % 2 == 0:
  print(0.5)
else:
  print(-(-N//2) / N)
