#include <fstream>
#include <algorithm>
using namespace std;
ifstream cin("scmax.in");
ofstream cout("scmax.out");

int n, v[100001], i, p[100001], s[100001], k;

bool comp(int a, int b)
{
    return v[a]<v[b];
}
int main()
{
    cin>>n;
    for(i=1; i<=n; i++)
    {
        cin>>v[i];
        p[i]=i;
    }
    sort(p+1, p+n+1, comp);
    for(i=1; i<=n; i++)
        if(p[i-1]<p[i] && v[p[i-1]]!=v[p[i]]) s[i]=++k;
        else s[i]=k;
    cout<<s[n]<<'\n';
    k=0;
    for(i=1; i<=n; i++)
        if(s[i]>k)
        {
            k=s[i];
            cout<<v[p[i]]<<" ";
        }
    return 0;
}