import java.util.*;
import java.lang.*;

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