#include <bits/stdc++.h>
using namespace std;
double arr[1000000];
map<double, long long> arr1;
int main() {
  long long total;
  cin >> total;
  double sum = 0;
  for (long long i = 1; i <= total; i++) {
    long long val;
    cin >> val;
    sum += val;
    arr[i] = val;
    arr1[val]++;
  }
  sum /= total;
  cout << arr1[sum] << endl;
  for (long long i = 1; i <= total; i++) {
    if (sum == arr[i]) cout << i << " ";
  }
  cout << endl;
}
