import sys
input = lambda: sys.stdin.readline().rstrip()

def main():
    n = int(input())
    if n % 2 == 0:
        print(n/2/n)
    else:
        print(((n//2)+1)/n)

if __name__ == '__main__':
    main() import sys sys input = lambda: sys.stdin.readline().rstrip() input lambda: sys.stdin.readline().rstrip() sys.stdin.readline().rstrip() sys.stdin.readline().rstrip sys.stdin.readline() sys.stdin.readline sys.stdin sys stdin readline rstrip def main():
    n = int(input())
    if n % 2 == 0:
        print(n/2/n)
    else:
        print(((n//2)+1)/n) main n = int(input()) n int(input()) int input() input if n % 2 == 0:
        print(n/2/n)
    else:
        print(((n//2)+1)/n) n % 2 == 0 n % 2 n 2 0 print(n/2/n) print n/2/n n/2 n 2 n print(((n//2)+1)/n) print ((n//2)+1)/n (n//2)+1 n//2 n 2 1 n if __name__ == '__main__':
    main() __name__ == '__main__' __name__ '__main__' main() main def main():
    n = int(input())
    if n % 2 == 0:
        print(n/2/n)
    else:
        print(((n//2)+1)/n) def main():
    n = int(input())
    if n % 2 == 0:
        print(n/2/n)
    else:
        print(((n//2)+1)/n) main input = lambda: sys.stdin.readline().rstrip() lambda: sys.stdin.readline().rstrip() input
import sys
input = lambda: sys.stdin.readline().rstrip()

def main():
    n = int(input())
    if n % 2 == 0:
        print(n/2/n)
    else:
        print(((n//2)+1)/n)

if __name__ == '__main__':
    main()