#include <stdio.h>
long int n, v[5001], best[5001], p[5001], maxim, k, L[5001], nr;

void afis(int i)
{
   maxim++;
   if (p[i] > 0)  afis(p[i]);
   if (!k){ printf("%d\n",maxim);k = 1;}
   printf("%d ",i);
}

int caut(int x)
{
   int p, u, m;
   p = 0; u = nr; m = (p+u)/2;
   while (p <= u)
   {
      if (v[L[m]] <= x &&  v[L[m+1]] > x) return m;
      else if (v[L[m+1]] < x) {p = m + 1; m = (p + u)/2;}
      else {u = m - 1; m = (p + u)/2;}
   }
   return nr;
}


int main()
{
   freopen("subsir2.in","r",stdin);
   freopen("subsir2.out","w",stdout);
   int i, j, poz;
   long val = 0; nr = 1;

   scanf("%ld",&n);
   for (i = 1; i <= n; i++) scanf("%ld", v + i);
   best[1] = 1; L[0] =  0; L[1] = 1;

   for (i = 2; i <= n; i++)
   {
      val = - 2000000;
      poz = caut(v[i]);
      p[i] = L[poz];
      best[i] = poz + 1;
      if (poz >= nr) nr = poz+1;
      if (v[i] < v[L[poz+1]] || !v[L[poz+1]])  L[poz + 1] = i;
   }
   poz = 0;
   for (i = nr; i >= 1; i--)
      if (poz < L[i])
      {
	 maxim = i;
	 poz = L[i];
      }
   afis(poz);
   return 0;
}