import java.util.Scanner;


public class Main_yukicoder87 {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        long n = sc.nextLong();

        int ret = 0;
        long tmp = 0;
        for (long i = 2015; i <= Math.min(2400, n); i++) {
        	if ((i % 4 == 0 && i % 100 != 0) || (i % 4 == 0 && i % 400 == 0)) {
        		tmp += 2;
        	} else {
        		tmp += 1;
        	}

        	if (tmp % 7 == 0) {
        		ret++;
        	}
        }

        if (n > 2400) {
        	int[] wed = new int[400 + 1];
        	for (long i = 2401; i <= 2800; i++) {
            	if ((i % 4 == 0 && i % 100 != 0) || (i % 4 == 0 && i % 400 == 0)) {
            		tmp += 2;
            	} else {
            		tmp += 1;
            	}

            	if (tmp % 7 == 0) {
            		wed[(int)(i - 2400)] = wed[(int)(i - 1 - 2400)] + 1;
            	} else {
            		wed[(int)(i - 2400)] = wed[(int)(i - 1 - 2400)];
            	}
        	}

        	ret += (n - 2400) / 400 * wed[400] + wed[(int)((n - 2400) % 400)];
        }

        System.out.println(ret);

        sc.close();
    }
}