n=int(input());print(1/2 if n%2==0 else (n//2+1)/n) n=int(input()) n int(input()) int input() input print(1/2 if n%2==0 else (n//2+1)/n) print 1/2 if n%2==0 else (n//2+1)/n n%2==0 n%2 n 2 0 1/2 1 2 (n//2+1)/n n//2+1 n//2 n 2 1 n n=int(input()) int(input()) n
n=int(input());print(1/2 if n%2==0 else (n//2+1)/n)