#include <fstream>
#include <vector>
#include <algorithm>
using namespace std;

ifstream fin("scmax.in");
ofstream fout("scmax.out");

size_t vecMax = 1;
vector<vector<int>> subSiruri;

void Inserare(int x, vector<vector<int>>& vecSubSiruri);

int main()
{
    int m, x;
    fin >> m;
    for (int i = 1; i <= m; ++i)
    { fin >> x; Inserare(x, subSiruri); }

    fout << subSiruri.size() << '\n';
    for (vector<int>& vec : subSiruri)
    {
        sort(vec.begin(), vec.end());
        fout << vec.front() << ' ';
    }

    fin.close();
    fout.close();
    return 0;
}

void Inserare(int x, vector<vector<int>>& vecSubSiruri)
{
    if (vecSubSiruri.empty()) { vecSubSiruri.push_back({ x }); return; }
    if (x > vecSubSiruri.back().back()) { vecSubSiruri.push_back({ x }); return; }

    int st = 0, dr = vecSubSiruri.size() - 1, mij, aux;

    while (st <= dr)
    {
        mij = (st + dr) / 2;
        if (x <= vecSubSiruri[mij].back()) { aux = mij; dr = mij - 1; }
        else { st = mij + 1; }
    }

    subSiruri[aux].push_back(x);
    vecMax = max(vecMax, subSiruri.size());
}