n=int(input())
if(n%2==0):
  print((n//2)/n)
else:
  print((n//2+1)/n) n=int(input()) n int(input()) int input() input if(n%2==0):
  print((n//2)/n)
else:
  print((n//2+1)/n) n%2==0 n%2 n 2 0 print((n//2)/n) print (n//2)/n n//2 n 2 n print((n//2+1)/n) print (n//2+1)/n n//2+1 n//2 n 2 1 n n=int(input()) int(input()) n
n=int(input())
if(n%2==0):
  print((n//2)/n)
else:
  print((n//2+1)/n)