#include <iostream>
using namespace std;
int main()
{
	int n,i=1,c=0;
	cin >> n;
	while(i<=n)
	{
	if(i%3 == 2 && i%5 == 3 && i%7 == 2)
	{
		c++;
	}
	i++;
	}
	cout << c;
}
/**************************************************************
	Problem: 1055
	User: xiaomingze
	Language: C++
	Result: Accepted
	Time:15 ms
	Memory:2072 kb
****************************************************************/