#include <bits/stdc++.h>
using namespace std;
double sum = 0.0;
int a[1000005], b[1000005];
int cnt = 0;
int main() {
  int n, i;
  scanf("%d", &n);
  for (i = 0; i < n; i++) {
    scanf("%d", a + i);
    sum += a[i];
  }
  sum /= n;
  for (i = 0; i < n; i++)
    if (a[i] == sum) {
      cnt++;
      b[cnt - 1] = i + 1;
    }
  printf("%d\n", cnt);
  if (cnt) printf("%d", b[0]);
  for (i = 1; i < cnt; i++) printf(" %d", b[i]);
  return 0;
}
