      PROGRAM oddsOfOddness
      IMPLICIT NONE
      INTEGER :: N
      
      INTEGER :: i, counterOdd, counterEven
      LOGICAL :: flag
      REAL :: ans
      READ*,N
      
      
      counterOdd = 0
      counterEven = 0
      flag = .true. !odd
      DO i = 1,N
        if(flag)then
          counterOdd = counterOdd + 1
        else
          counterEven = counterEven + 1
        end if
        
        flag = .not.(flag)
      END DO
      
      ans = real(counterOdd)/real(N)
      
      print*,ans
      
      
      
      
      END PROGRAM
      