import java.math.*; import java.util.*; class Main { static int gcd(int a,int b){ if(b==0) return a; else return gcd(b, a%b); } public static void main(String[] args) { Scanner sc = new Scanner(System.in); int n = sc.nextInt(); int ans=0; for(int i=1;i*in/4) continue; ans++; } } System.out.println(ans); } }