#include <fstream>

using namespace std;
ifstream f("subsir2.in");
ofstream g("subsir2.out");
int n,a[5001],i,l,ind[5001],poz;
int caut(int val)
{
  int st=1,dr=l,m;
  while(st<=dr)
  {
    m=(st+dr)/2;
    if (val>a[ind[m]] && val<a[ind[m+1]]) return m;
    else if (val>a[ind[m]]) st=m+1;
    else dr=m-1;
  }
  return 1;
}
int main()
{
    f>>n;
    for (i=1;i<=n;i++)
      f>>a[i];
    l=1,ind[1]=1;
    for (i=2;i<=n;i++)
      if (a[i]>a[ind[l]])
      l++,ind[l]=i;
     else
     {
       poz=caut(a[i]);
       ind[poz]=i;
     }
   g<<l<<'\n';
   for (i=1;i<=l;i++)
    g<<ind[i]<<' ';
    return 0;
}