import java.util.Scanner;

public 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);
        }
    }
}
/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