#include <iostream>
#include <fstream>
#include <cstring>
#include <vector>
#include <map>

using namespace std;

int n, ms, res;
map<int, bool> g[3000];
map<int, bool> og[3000];
bool vis[3000];
bool dn[3000];

int gg(int cs)
{
    for (int i = 0; i < n; i++)
    {
        g[i].clear();
        copy(og[i].begin(), og[i].end(), g[i].begin());
        dn[i] = false;
    }

    int rc = 0;
    bool nr = false;
    while (!nr)
    {
        nr = true;
        for (int i = 0; i < n; i++)
        {
            if (g[i].size() >= cs || dn[i])
                continue;

            dn[i] = true;
            rc++;

            for (map<int, bool>::iterator j = g[i].begin(); j != g[i].end(); j++)
            {
                cout << j->first;
//                g[j->first].erase(i);
            }
        }
    }

    return rc;
}

void bs(int s, int e)
{
    if (s > e)
        return;

    int mid = (s + e) / 2;
    int rc = gg(mid);

    if (rc < n)
        bs(s, mid - 1);
    else
    {
        ms = mid;
        bs(mid + 1, e);
    }
}

int maximum_deevs(vector<int> v)
{
    n = v.size();
    res = 0;
    for (int i = 0; i < n; i++)
        g[i].clear();
    memset(vis, 0, sizeof(vis));

    int cm;
    for (int i = 0; i < n; i++)
    {
        cm = 0;
        for (int j = i + 1; j < n; j++)
        {
            if (v[j] >= cm)
            {
                og[i][j] = true;
                og[j][i] = true;
                cm = v[j];
            }
        }
    }

    ms = 0;
    bs(0, n - 1);

    return res;
}

int main()
{
    ifstream cin("in.txt");

    int n, curr;

    cin >> n;

    vector<int> iv;
    for (int i = 0; i < n; i++)
    {
        cin >> curr;
        iv.push_back(curr);
    }

    cout << maximum_deevs(iv);

    return 0;
}