import java.util.*;

public class Main {
    public void main(Scanner sc) {
        int n = sc.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);
        }
    }

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

/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz