#include <bits/stdc++.h>
using namespace std;
int a[11451419];
int main() {
  int n;
  scanf("%d", &n);
  int cnt = 0;
  for (int i = 1; i <= n; i++) {
    scanf("%d", &a[i]);
    cnt += a[i];
  }
  double pj = double(cnt) / double(n);
  cnt = 0;
  for (int i = 1; i <= n; i++) {
    if (double(a[i]) == pj) cnt++;
  }
  printf("%d\n", int(cnt));
  for (int i = 1; i <= n; i++) {
    if (double(a[i]) == pj) printf("%d ", i);
  }
}
