#include <fstream>
#include <climits>
#include <iostream>
using namespace std;
ifstream f("subsir2.in");
ofstream g("subsir2.out");
int n,i,v[5001],l[5001],ok,k,maxim,elem,minim,copie,j;
int main()
{
    f>>n;
    for(i=1;i<=n;i++)
        f>>v[i];
    l[n]=1;
    for(i=n-1;i>=1;i--)
    {
         minim=INT_MAX;
         maxim=INT_MAX;
        for(j=i+1;j<=n;j++)
        if(v[i]<v[j]&&l[j]<minim&&v[j]<maxim){minim=l[j];maxim=v[j];}

       if(minim!=INT_MAX) l[i]=minim+1;
       else l[i]=1;
    }


   maxim=l[1];

    for(i=2;i<=n;i++)
       {
           ok=1;
           for(j=i-1;j>=1;j--)
            if(l[i]<l[j])ok=0;

           if(ok==1){if(l[i]<maxim)maxim=l[i];}
       }



    g<<maxim<<'\n';

    elem=INT_MIN;
    int poz=0;

    while(maxim)
    {

    minim=INT_MAX;
  //cout<<maxim;
    for(i=1;i<=n;i++)
    if(l[i]==maxim&&v[i]>elem){if(v[i]<minim){poz=i;minim=v[i];copie=i;}}

    g<<copie<<" ";
    elem=v[copie];
    maxim--;


    }


    return 0;
}