#include <algorithm>
#include <bitset>
#include <chrono>
#include <complex>
#include <cstdint>
#include <cstring>
#include <fstream>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <ostream>
#include <queue>
#include <random>
#include <regex>
#include <set>
#include <sstream>
#include <string>
#include <tuple>
#include <utility>
#include <vector>
#define all(r) r.begin(),r.end()
using namespace std;
constexpr int32_t INF = 0x3F3F3F3F;
using ll = int64_t;
using vll = vector<ll>;
struct Solution {
    void solve(std::istream& in, std::ostream& out) {
        ll n;
        in >> n;
        vll table;
        for (int k = 0; k < INF; k++) {
            ll t = k * (k + 1) / 2;
            if (t < 0) {
                break;
            }
            table.emplace_back(t);
        }
        ll len = table.size();
        vll dp(n + 1);
        fill(all(dp), -1);
        dp[0] = 0;
        for (int i = 0; i < len; i++) {
            for (int j = table[i]; j <= n; j++) {
                if (dp[j] >= 0) {
                    dp[j] = table[i];
                }
                else {
                    dp[j] = dp[j - table[i]] - 1;
                }
            }
        }
        out << -dp[n] << '\n';
    }
};
void solve(std::istream& in, std::ostream& out) {
    out << std::setprecision(12);
    Solution solution;
    solution.solve(in, out);
}
int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    istream& in = cin;
    ostream& out = cout;
    solve(in, out);
    return 0;
}