//infoarena subsir2
// http://infoarena.ro/problema/subsir2
//O(n^2)
#include <cstdio>
#include <cstdlib>

#define INF 0x7FFFFFFF
#define min(a,b) ((a) < (b) ? (a) : (b))
#define max(a,b) ((a) > (b) ? (a) : (b))

using namespace std;

#define MAX 5000

int v[MAX], N, Lmin, L[MAX], T[MAX],rez[MAX];

void calc()
{
    L[N-1] = 1;
    T[N-1] = N-1;

    for (int i = N-2; i>=0; i--)
    {
        int vmin = INF, l = INF, poz=INF;
        for (int j = i+1; j<N; j++)
        {

            if (v[j] >= v[i] && v[j] < vmin && L[j] <= l)
            {
                l = L[j];
                if ( poz == INF )
                    poz = j;
                else
                    if ( L[j] == l && v[j] <= v[poz] )
                        poz = j;
            };

            if (v[j] >=v[i] && v[j] <vmin) vmin = v[j];
        };
        if (l==INF) { l =0; poz = i; };
        L[i] = l + 1;
        T[i] = poz;
    };
};

void refa(int poz, int &nr)
{
    for ( int i = poz; ; i = T[i])
    {
        rez[nr++] = i;
        if (T[i] == i ) break;
    };
};

int check(int nr)
{
    for (int i =0; i<rez[0]; i++)
        if (v[i] <= v[rez[0]])
            return 0;
    for (int i = rez[nr-1]+1; i<N; i++)
        if (v[i] >= v[rez[nr-1]])
            return 0;

    for (int i = 1 ; i<nr; i++)
            for (int j = rez[i-1]+1; j<rez[i]; j++)
                if (v[j] >= v[rez[i-1]] && v[j] <= v[rez[i]])
                    return 0;
    return 1;
};



int main()
{
    freopen("subsir2.in", "r", stdin);
    freopen("subsir2.out", "w", stdout);

    scanf("%d\n", &N);
    for (int i = 0; i<N; i++)
        scanf("%d", &v[i]);

    calc();
    int vmin,k=0,poz1=0, poz2;
    Lmin = L[0];  vmin = v[0];
    for (int i=1; i<N; i++)
    {
        if (v[i] < vmin ) vmin = v[i]+k;
        else if (v[i] == vmin) { vmin++; k =1; };
        if (v[i] == vmin && L[i] <= Lmin)
        {
            Lmin = L[i];
            poz1 = i;
        };
    };
    poz2=0;
    for (int i = 1; i<N; i++)
        if (L[i] == Lmin && v[i] < v[poz2])
            poz2 = i;

    int nr=0;
    refa(poz2,nr);
    if (nr != Lmin || !check(nr))
    {
        nr=0;
        refa(poz1,nr);
    };


    printf("%d\n", Lmin);
    for (int i = 0; i<nr; i++)
        printf("%d ", rez[i]+1);


    fclose(stdin);
    fclose(stdout);
    return 0;
};