a = int(input())
b = a % 2
if b == 0:
  my_result = 0.5
else:
  my_result = (a + 1) / (2 * a)
print(my_result) a = int(input()) a int(input()) int input() input b = a % 2 b a % 2 a 2 if b == 0:
  my_result = 0.5
else:
  my_result = (a + 1) / (2 * a) b == 0 b 0 my_result = 0.5 my_result 0.5 my_result = (a + 1) / (2 * a) my_result (a + 1) / (2 * a) a + 1 a 1 2 * a 2 a print(my_result) print my_result a = int(input()) int(input()) a my_result = 0.5 0.5 my_result my_result = (a + 1) / (2 * a) (a + 1) / (2 * a) my_result b = a % 2 a % 2 b
a = int(input())
b = a % 2
if b == 0:
  my_result = 0.5
else:
  my_result = (a + 1) / (2 * a)
print(my_result)