n=int(input())
c=0
for i in range(1,n+1):
  if i%2!=0:
    c+=1 
print("{0:.10f}".format(c/n)) n=int(input()) n int(input()) int input() input c=0 c 0 for i in range(1,n+1):
  if i%2!=0:
    c+=1  i range(1,n+1) range 1 n+1 n 1 if i%2!=0:
    c+=1  i%2!=0 i%2 i 2 0 c+=1 c 1 print("{0:.10f}".format(c/n)) print "{0:.10f}".format(c/n) "{0:.10f}".format "{0:.10f}" format c/n c n n=int(input()) int(input()) n c=0 0 c c+=1 1 c
n=int(input())
c=0
for i in range(1,n+1):
  if i%2!=0:
    c+=1 
print("{0:.10f}".format(c/n))