#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;

bool solution;
vector<long int> v;
vector<bool> b;
long int N;

void gensubset(int i)
{
	if (solution)
		return;
	if (i < v.size())
	{
		b[i] = false;
		gensubset(i + 1);
		b[i] = true;
		gensubset(i + 1);
	}
	else
	{
		long int S  = 0;
		for (long int i = 0; i < v.size(); ++i)
		{
			if (b[i])
				S += v[i];
			if ((S%N == 0) && (S>0))
			{
				int k = 0;
				solution = true;
				for (long int i = 0; i < v.size(); ++i)
				{

					if (b[i])
						k++;
				}
				cout << k << endl;
				for (long int i = 0; i < v.size(); ++i)
				{

					if (b[i])
						cout << i + 1 << " ";
				}
				cout << endl;
			}
		}
	}

}


int main(){
	solution = false;
	cin >> N;

	v.resize(N);
	b.resize(N);
	for (long int i = 0; i < N; i++)
		cin >> v[i];
	

	gensubset(0);

}