#include <iostream>
using namespace std;

int main() {
    int n;
    cin >> n;

    int buses = (n + 29) / 30;
    cout << buses << endl;

    return 0;
}    
/**************************************************************
	Problem: 1632
	User: linmiaoling
	Language: C++
	Result: Accepted
	Time:6 ms
	Memory:2072 kb
****************************************************************/