#include <bits/stdc++.h>
using namespace std;
ifstream f("subsir2.in");
ofstream g("subsir2.out");
int i,n,lmx,a[5001],j,nr,l[5001],mnm,ii,poz,k,p;
int main()
{
    f>>n;
    for(i=1; i<=n; i++)
        f>>a[i];
    l[n]=1;
    for(i=n-1; i>=1; i--)
    {
        lmx=0;
        for(j=i+1; j<=n; j++)
            if(a[i]<a[j]&&l[j]>lmx)lmx=l[j];
        l[i]=lmx+1;
        if(l[i]>lmx)lmx=l[i];
    }
    g<<lmx<<'\n';
    poz=1;
    for (k=lmx; k>=1; k--)
    {
        mnm=1000000;
        for (i=poz; i<=n; i++)
            if (mnm>a[i] && l[i]==k)
            {
                p=i;
                mnm=a[i];
            }
        poz=p;
        g<<poz<<" ";
    }
    return 0;
}