#include <bits/stdc++.h>

using namespace std;
ifstream in("scmax.in");
ofstream out("scmax.out");
#define cin in
#define cout out
deque <int>deq;
deque <int>deq2;

void afis(deque<int>x)
{
    int n=x.size();
    cout<<n;
    while (n>0)
    {
        cout<<x.back();
        x.pop_back();
        n--;
    }
}

void e(int x)
{
    if (deq.back()<x){
        if (deq2.empty())
        deq2.push_front(x);
        }
    else if (deq.front()<x)
        deq.push_front(x);
    if (deq2.front()<x)
        deq2.push_front(x);
}

void cit()
{
    int n,x;
    cin>>n;
    for (int i=1;i<=n;i++)
    {
        cin>>x;
        e(x);
    }
}
int main()
{
    cit();
    if (deq.size()>deq2.size())
        afis(deq);
        else
        afis(deq2);
    return 0;
}