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