import java.util.Scanner;

class Main {
	public static void main(String[] args) {
		Scanner stdIn = new Scanner(System.in);
		int n = stdIn.nextInt();

		if (n < 105) 
			System.out.println(0);
		else if (n < 135) 
			System.out.println(1);
		else if (n < 165) 
			System.out.println(2);
		else if (n < 189)
			System.out.println(3);
		else if (n < 195)
			System.out.println(4);
		else
			System.out.println(5);
	}
} import java.util.Scanner; Scanner java.util class Main {
	public static void main(String[] args) {
		Scanner stdIn = new Scanner(System.in);
		int n = stdIn.nextInt();

		if (n < 105) 
			System.out.println(0);
		else if (n < 135) 
			System.out.println(1);
		else if (n < 165) 
			System.out.println(2);
		else if (n < 189)
			System.out.println(3);
		else if (n < 195)
			System.out.println(4);
		else
			System.out.println(5);
	}
} Main public static void main(String[] args) {
		Scanner stdIn = new Scanner(System.in);
		int n = stdIn.nextInt();

		if (n < 105) 
			System.out.println(0);
		else if (n < 135) 
			System.out.println(1);
		else if (n < 165) 
			System.out.println(2);
		else if (n < 189)
			System.out.println(3);
		else if (n < 195)
			System.out.println(4);
		else
			System.out.println(5);
	} main {
		Scanner stdIn = new Scanner(System.in);
		int n = stdIn.nextInt();

		if (n < 105) 
			System.out.println(0);
		else if (n < 135) 
			System.out.println(1);
		else if (n < 165) 
			System.out.println(2);
		else if (n < 189)
			System.out.println(3);
		else if (n < 195)
			System.out.println(4);
		else
			System.out.println(5);
	} Scanner stdIn = new Scanner(System.in); stdIn new Scanner(System.in) int n = stdIn.nextInt(); n stdIn.nextInt() stdIn.nextInt stdIn if (n < 105) 
			System.out.println(0);
		else if (n < 135) 
			System.out.println(1);
		else if (n < 165) 
			System.out.println(2);
		else if (n < 189)
			System.out.println(3);
		else if (n < 195)
			System.out.println(4);
		else
			System.out.println(5); n < 105 n 105 System.out.println(0) System.out.println System.out System System.out 0 if (n < 135) 
			System.out.println(1);
		else if (n < 165) 
			System.out.println(2);
		else if (n < 189)
			System.out.println(3);
		else if (n < 195)
			System.out.println(4);
		else
			System.out.println(5); n < 135 n 135 System.out.println(1) System.out.println System.out System System.out 1 if (n < 165) 
			System.out.println(2);
		else if (n < 189)
			System.out.println(3);
		else if (n < 195)
			System.out.println(4);
		else
			System.out.println(5); n < 165 n 165 System.out.println(2) System.out.println System.out System System.out 2 if (n < 189)
			System.out.println(3);
		else if (n < 195)
			System.out.println(4);
		else
			System.out.println(5); n < 189 n 189 System.out.println(3) System.out.println System.out System System.out 3 if (n < 195)
			System.out.println(4);
		else
			System.out.println(5); n < 195 n 195 System.out.println(4) System.out.println System.out System System.out 4 System.out.println(5) System.out.println System.out System System.out 5 String[] args args
import java.util.Scanner;

class Main {
	public static void main(String[] args) {
		Scanner stdIn = new Scanner(System.in);
		int n = stdIn.nextInt();

		if (n < 105) 
			System.out.println(0);
		else if (n < 135) 
			System.out.println(1);
		else if (n < 165) 
			System.out.println(2);
		else if (n < 189)
			System.out.println(3);
		else if (n < 195)
			System.out.println(4);
		else
			System.out.println(5);
	}
}