#include<bits/stdc++.h>
using namespace std;
int main(){
	int g=0,i=1,n;
	cin>>n;
	while(i<=n){
		if(i%3==2&&i%5==3&&i%7==2)
		g=g+1;
		i++;
	}
	cout<<g;
	return 0;
}

/**************************************************************
	Problem: 1055
	User: tangkaixuan
	Language: C++
	Result: Accepted
	Time:7 ms
	Memory:2072 kb
****************************************************************/