N=int(input())
t=N//2
if N%2==1:
  t+=1
print(t/N) N=int(input()) N int(input()) int input() input t=N//2 t N//2 N 2 if N%2==1:
  t+=1 N%2==1 N%2 N 2 1 t+=1 t 1 print(t/N) print t/N t N t=N//2 N//2 t t+=1 1 t N=int(input()) int(input()) N
N=int(input())
t=N//2
if N%2==1:
  t+=1
print(t/N)