#include <fstream>

using namespace std;

ifstream fin("subsir2.in");
ofstream fout("subsir2.out");

int n, m;
int v[5005];

int poz[5005];
int pred[5005];

int caut_bin(int k)
{
    int i = 0, pas = 1<<30;
    while (pas != 0) {
        if (i  + pas <= m && v[poz[i + pas]] < k) i+=pas;
        pas /= 2;
    }
    return i;
}

void afisare(int p)
{
    if (pred[p] != 0) {
        afisare(pred[p]);
    }
    fout<<p<<' ';
}

int main()
{
    fin>>n;
    for (int i = 1; i <= n; i++) {
        fin>>v[i];
    }
    for (int i = 1; i <= n; i++) {
        int j = caut_bin(v[i]);
        if (j == m) {
            m++;
        }
        poz[j + 1] = i;
        pred[i] = poz[j];
    }
    fout<<m<<'\n';
    afisare(poz[m]);
}