#include <bits/stdc++.h>
using namespace std;
double a[200005];
int out[200005];
int main() {
  int n;
  scanf("%d", &n);
  double sum = 0;
  for (int i = 0; i < n; i++) {
    scanf("%lf", &a[i]);
    sum += a[i];
  }
  int num = 0;
  for (int i = 0; i < n; i++) {
    sum -= a[i];
    if (a[i] == sum / (n - 1)) out[num++] = (i + 1);
    sum += a[i];
  }
  printf("%d\n", num);
  for (int i = 0; i < num; i++) printf("%d ", out[i]);
  return 0;
}
