#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
ll GCD(ll x,ll y){
    if(y == 0) return x;
    else return GCD(y,x%y);
}

int main() {
    int n;
    cin >> n;
    cout << n / 3 << endl;
}


#include<iostream>
#include<string>
#include<vector>

using namespace std;

int main()
{
    int a;

    cin>>a;
    a += (a*a) + (a*a*a);
    cout<<a;
    cout<<endl;
    return 0;
}