#include <iostream>
#include <fstream>
#include <algorithm>

#define Nmax 100005
//#define Nmax_Fr 2000000005

using namespace std;

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

long long Dp[Nmax];
int k;
int Fr[Nmax];

int main()
{
    ios::sync_with_stdio(0);
    fin.tie(0);
    fout.tie(0);
    int n;
    fin >> n;
    int x;
    fin >> x;
    Dp[++ k] = x;
    Fr[x] = 1;
    n --;
    while(n)
    {
        int y;
        fin >> y;
        if(y > Dp[k] && Fr[y] == 0)
        {
            Dp[++ k] = y;
            n --;
            continue;
        }
        else if(y < Dp[k] && Fr[y] == 0)
        {
            int upper = upper_bound(Dp + 1, Dp + k + 1, y) - Dp;
            Dp[upper] = y;
            Fr[y] = 1;
            n --;
            continue;
        }
        else if (Fr[y] == 1)
        {
            n --;
            continue;
        }
        n --;
    }
    fout << k << "\n";
    for(int i = 1; i <= k; i ++)
        fout << Dp[i] << " ";
    return 0;
}