#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#pragma GCC optimize("-ffloat-store")
using namespace std;
clock_t time_p = clock();
void aryanc403() {}
const long long int INF = 0xFFFFFFFFFFFFFFFL;
long long int seed;
mt19937 rng(seed = chrono::steady_clock::now().time_since_epoch().count());
inline long long int rnd(long long int l = 0, long long int r = INF) {
  return uniform_int_distribution<long long int>(l, r)(rng);
}
class CMP {
 public:
  bool operator()(pair<long long int, long long int> a,
                  pair<long long int, long long int> b) {
    return !(a.first < b.first || (a.first == b.first && a.second <= b.second));
  }
};
void add(map<long long int, long long int> &m, long long int x,
         long long int cnt = 1) {
  auto jt = m.find(x);
  if (jt == m.end())
    m.insert({x, cnt});
  else
    jt->second += cnt;
}
void del(map<long long int, long long int> &m, long long int x,
         long long int cnt = 1) {
  auto jt = m.find(x);
  if (jt->second <= cnt)
    m.erase(jt);
  else
    jt->second -= cnt;
}
bool cmp(const pair<long long int, long long int> &a,
         const pair<long long int, long long int> &b) {
  return a.first < b.first || (a.first == b.first && a.second < b.second);
}
const long long int mod = 1000000007L;
long long int T, n, i, j, k, in, cnt, l, r, u, v, x, y;
long long int m;
string s;
vector<long long int> a, vis, b, p;
void dfs(long long int u, long long int par) {
  if (!b.empty()) return;
  if (vis[u]) {
    if (vis[u] != T) return;
    swap(u, par);
    ;
    b.push_back(par);
    while (u != par) {
      b.push_back(u);
      u = p[u];
    }
    return;
  }
  vis[u] = T;
  p[u] = par;
  dfs(a[u], u);
}
int main(void) {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  long long int tt;
  cin >> tt;
  while (tt--) {
    cin >> n;
    a.clear();
    a.reserve(n);
    a.push_back(0);
    vis.clear();
    vis.resize(n + 1, 0);
    p.clear();
    p.resize(n + 1, 0);
    b.clear();
    for (i = (1); i <= (n); ++i) {
      cin >> in;
      if (in == 0) b.push_back(i);
      a.push_back(i - in);
    };
    for (i = (1); i <= (n); ++i) {
      if (vis[i] || !b.empty()) continue;
      T = i;
      dfs(i, 0);
    }
    cout << (int)(b).size() << "\n";
    for (auto x : b) cout << x << " ";
    cout << "\n";
  }
  aryanc403();
  return 0;
}
