import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		int N = scan.nextInt();
		scan.close();
		int t = N - 2014;
		int h = zeller(2014, 7, 23);
		int cnt = 0;
		for(int i = 0; i < 400; i++) {
			if(h == zeller(2015 + i, 7, 23)) {
				cnt ++;
			}
		}
		int k = t / 400;
		int ans = k * cnt;
		int s = 2015 + k *  400;

		for(int i = s; i <= N; i++) {
			if(h == zeller(i, 7, 23)) {
				ans++;
			}
		}
		System.out.println(ans);

	}
	static int zeller(int y, int m, int d) {
		int t1 = d;
		int t2 = (26 * (m + 1)) / 10;
		int t3 = y % 100 + (y % 100) / 4;
		int t4 = 5 * (y / 100) + (y / 100) / 4;
		return (t1 + t2 + t3 + t4) % 7;
	}
}