#include <bits/stdc++.h>

using namespace std;

const int inf = 1e9;

int n;
vector<vector<pair<int, int>>> g;

struct vrt {
    int ind;
    int real_dist;
    int set_dist;

    vrt() {
        ind = -1;
    }

    vrt(int i) {
        ind = i;
        real_dist = inf;
        set_dist = inf;
    }

    vrt(int a, int b, int c) {
        ind = a;
        real_dist = b;
        set_dist = c;
    }

    bool operator <(const vrt &other) const {
        return set_dist < other.set_dist;
    }
};

int solve(int start) {
    vector<int> p(n, -1);
    vector<int> d(n, inf);
    set<vrt> tmp;
    vector<vrt> uu;
    for (int i = 0; i < n; i++) {
        if (i == start) {
            tmp.insert(vrt(i, 0, 0));
            uu.push_back(vrt(i, 0, 0));
        } else {
            tmp.insert(vrt(i));
            uu.push_back(vrt(i));
        }
    }
    while (!tmp.empty()) {
        int cur = (*tmp.begin()).ind;
        tmp.erase(tmp.begin());
        for (auto [u, w] : g[cur]) {
            if (uu[u].real_dist > uu[cur].real_dist + w) {
                tmp.erase({d[t.first], t.first});
                p[t.first] = cur;
                d[t.first] = d[cur] + t.second;
                tmp.insert({d[t.first], t.first});
            }
        }
    }
    cerr << "d " << d[1] << endl;
    cerr << "p " << p[1] << endl;
    int ans = 0;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            if (p[j] == i) {
                int b = inf;
                for (auto [u, w] : g[i]) {
                    if (u == j) {
                        b = min(b, w);
                    }
                }
                ans += b;
                cerr << "uu " << j + 1 << ' ' << b << endl;
            }
        }
    }
    return ans;
}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

#ifdef LOCAL
    assert(freopen("input.txt", "r", stdin));
    assert(freopen("output.txt", "w", stdout));
#endif

    //    int m;
    //    cin >> n >> m;
    //    g.resize(n);
    //    for (int i = 0; i < m; i++) {
    //        int u, v, c;
    //        cin >> u >> v >> c;
    //        u--;
    //        v--;
    //        g[u].push_back({v, c});
    //        g[v].push_back({u, c});
    //    }
    //    auto res = solve(0);
    //    cout << res;

    const int lim = 2e9;

    vector<int> ans = {0, 1};
    for (int i = 1; i < lim; i++) {
        for (int j = 0; j < ans[i]; j++) {
            if (ans.size() < lim) {
                ans.push_back(i);
            } else {
                break;
            }
        }
    }
    //    for (int i = 1; i < lim; i++) {
    //        cout << ans[i] << ' ';
    //    }
    cout << ans.back() << endl;
}