#include<bits/stdc++.h>
using namespace std;
int main(){
	int n,h;
	cin>>n;
	h=n/30;
	if (n%30!=0){
		h=h+1;
	}
	cout<<h<<endl;
	return 0;
}
/**************************************************************
	Problem: 1632
	User: xiaojingxuan
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2072 kb
****************************************************************/