#define _USE_MATH_DEFINES
#include <cstdio>
#include <iostream>
#include <sstream>
#include <fstream>
#include <iomanip>
#include <algorithm>
#include <cmath>
#include <complex>
#include <string>
#include <vector>
#include <list>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <bitset>
#include <numeric>
#include <limits>
#include <climits>
#include <cfloat>
#include <functional>
#include <iterator>
using namespace std;

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

    vector<int> v;
    for(int k=1; ; ++k){
        int x = k * (k + 1) / 2;
        if(x > n)
            break;
        v.push_back(x);
    }
    reverse(v.begin(), v.end());

    int ans = 0;
    for(int x : v){
        if(x <= n){
            n -= x;
            ++ ans;
        }
    }
    cout << ans << endl;

    return 0;
}