import java.util.*;


public class Main {
	
	static boolean isLeapYear(long y) {
		return y % 4 == 0 && (y % 100 != 0 || y % 400 == 0);
	}
	
	static long func(long n) {
		long cnt1 = 0;
		long LOOP = 400 * 7;
		long d = 0;
		for(int i = 1; i <= LOOP && 2014 + i <= n; i++) {
			d += isLeapYear(i + 2014) ? 2 : 1;
			if(d % 7 == 0) cnt1++;
			if(2014 + i == n) {
				return cnt1;
			}
		}
		
		long ans = (n - 2015) / LOOP * cnt1;
		d = d % 7 * (n - 2015) / LOOP % 7;

		for(long i = (n - 2015) / LOOP * LOOP + 2015; i <= n; i++) {
			d += isLeapYear(i) ? 2 : 1;
			if(d % 7 == 0) ans++;
		}
		
		return ans;
	}

	public static void main(String[] args) {
		/*
		for(int i = 2015; i <= 10000; i++) {
			int ans = 0;
			int d = 0;
			for(int j = 2015; j <= i; j++) {
				d += isLeapYear(j) ? 2 : 1;
				if(d % 7 == 0) ans++;
			}
			if(ans != func(i)) {
				System.err.println(i + " " + ans + " " + func(i));
			}
		}
		if(true) return;
		*/
		try(final Scanner sc = new Scanner(System.in)) {
			System.out.println(func(sc.nextLong()));
		}
	}

}