#include <iostream>
#include <set>
using namespace std;
set <int> S[40005];
int V[40005];
int j,k,ok,col,tmp,N,i;
int main()
{
    cin>>N;
    for(i=1;i<=N;i++)
    {
        cin>>V[i];
        V[i]%=N;
        if(S[V[i]].empty())
            S[V[i]].insert(i);
        for(j=0;j<N;j++)
        {
            if(j<V[i])
            {
                if(!S[j-V[i]+N].empty())
                    if(S[j].empty())
                    {
                        for(set<int> ::iterator it=S[j-V[i]+N].begin();it!=S[j-V[i]+N].end();it++)
                            S[j].insert(*it);
                        S[j].insert(i);
                    }
            }
            else if(j>V[i])
            {
                if(!S[j-V[i]].empty())
                    if(S[j].empty())
                    {
                        for(set<int> ::iterator it=S[j-V[i]].begin();it!=S[j-V[i]].end();it++)
                            S[j].insert(*it);
                        S[j].insert(i);
                    }
            }
        }
        if(!S[0].empty())
            break;
    }
    cout<<S[0].size()<<"\n";
    for(set<int>::iterator it=S[0].begin();it!=S[0].end();it++)
        cout<<*it<<" ";
    return 0;
}