#include <bits/stdc++.h>
const int N = 200005;
int a[N], b[N], s, i, n, m;
int main() {
  scanf("%d", &n);
  s = m = 0;
  for (i = 1; i <= n; i++) scanf("%d", &a[i]), s += a[i];
  for (i = 1; i <= n; i++)
    if (a[i] * n == s) b[++m] = i;
  printf("%d\n", m);
  for (i = 1; i <= m; i++) printf("%d ", b[i]);
  printf("\n");
}
