#include<iostream> 

using namespace std;

int main()
{
	
	int n,sum=0;
	cin>>n;
	int i=1;
	while(i<=n){
		if(i%3==2 && i%5==3 && i%7==2)sum++;
		i++;
	}
	
	cout<<sum<<endl;
	return 0;
}
/**************************************************************
	Problem: 1055
	User: 231308061
	Language: C++
	Result: Accepted
	Time:6 ms
	Memory:2072 kb
****************************************************************/