#include<cstdio>
#include<algorithm>
#include<iostream>
using namespace std;
const int inf = (1<<31)-1;
const int nmax = 100005;
int n,i,sol,cnt,poz,a[nmax],v[nmax],o[nmax],s[nmax];
int main()
{
    cin >> n;
    for(i=1;i<=n;i++)
    {
        cin>>a[i]; v[i]=inf;
        poz=lower_bound(v+1,v+i+1,a[i])-(v+1)+1;
        sol=max(sol,poz);
        v[poz]=a[i]; o[i]=poz;
    }
    cout<<sol<<endl; cnt=sol;
    for(i=n;i;i--)
        if(o[i]==sol) s[sol--]=a[i];
    for(i=1;i<=cnt;i++) cout<<s[i]<<" ";
    for(i=1;i<=cnt;i++) cout<<v[i]<<" ";
    return 0;
}