#include <iostream>
using namespace std;
 
int main() {
    int n;
    cin >> n;
 
    int buses = (n + 29) / 30;
    cout << buses << endl;
 
    return 0;
}    
/**************************************************************
	Problem: 1632
	User: linzihang
	Language: C++
	Result: Accepted
	Time:9 ms
	Memory:2072 kb
****************************************************************/