/*
ID: cristicretan
PROG: Subsir crescator maximal
LANG: C++14
*/
#include <iostream>
#include <fstream>
#include <cmath>
#define NMax 100001
//#define f cin
//#define g cout
using namespace std;

ifstream f("scmax.in");
ofstream g("scmax.out");

int n, a[NMax], ans, sol[NMax];

int main()
{
    f >> n;
    ans = -1;
    for(int i = 0; i < n; ++i)
    {
        f >> a[i];
        if(i > 0 && a[i] > a[i - 1])
        {
            sol[++ans] = a[i - 1];
            sol[++ans] = a[i];
        }
        else if(i > 0 && a[i] == a[i - 1]) continue;
        else ans = -1;
    }

    for (int i = 0; i < ans; ++i)
       {
           for(int j = ans; j > i; --j)
             if (sol[i] == sol[j])
               {
                  sol[j] = sol[j + 1];
                  --ans;
               }
       }

    g << ans + 1 << '\n';
    for(int i = 0; i <= ans; ++i)
        g << sol[i] << " ";
    return 0;
}