#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using uint = unsigned int;
using ull = unsigned long long;
template <class T>
bool set_max(T &a, const T &b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
template <class T>
bool set_min(T &a, const T &b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
template <typename A, typename B>
string to_string(pair<A, B> p);
template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p);
template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p);
string to_string(const string &s) { return '"' + s + '"'; }
string to_string(const char *s) { return to_string((string)s); }
string to_string(bool b) { return (b ? "true" : "false"); }
string to_string(vector<bool> v) {
  bool first = true;
  string res = "{";
  for (int i = 0; i < static_cast<int>(v.size()); i++) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(v[i]);
  }
  res += "}";
  return res;
}
template <size_t N>
string to_string(bitset<N> v) {
  string res = "";
  for (size_t i = 0; i < N; i++) {
    res += static_cast<char>('0' + v[i]);
  }
  return res;
}
template <typename A>
string to_string(A v) {
  bool first = true;
  string res = "{";
  for (const auto &x : v) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(x);
  }
  res += "}";
  return res;
}
template <typename A, typename B>
string to_string(pair<A, B> p) {
  return "(" + to_string(p.first) + ", " + to_string(p.second) + ")";
}
template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " +
         to_string(get<2>(p)) + ")";
}
template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " +
         to_string(get<2>(p)) + ", " + to_string(get<3>(p)) + ")";
}
void debug_out() { cerr << endl; }
template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
  cerr << " " << to_string(H);
  debug_out(T...);
}
const int N = 3e5 + 10;
const int MOD = 1e9 + 7;
const double eps = 1e-6;
const ll INF = 1e18;
const int inf = 1e9;
int a[N];
void solve() {
  int n;
  cin >> n;
  int sum = 0;
  for (int i = 1; i <= n; i++) {
    cin >> a[i];
    sum += a[i];
  }
  if (sum % n) {
    cout << "-1\n";
    return;
  }
  int avg = sum / n;
  vector<tuple<int, int, int>> ops;
  auto move = [&](int i, int j, int x) {
    assert(a[i] >= x * i);
    ops.emplace_back(i, j, x);
    a[j] += x * i;
    a[i] -= x * i;
  };
  for (int i = 2; i <= n; i++) {
    int x = (i - a[i] % i) % i;
    if (x > 0) {
      move(1, i, x);
    }
    assert(a[i] % i == 0);
    move(i, 1, a[i] / i);
  }
  for (int i = 2; i <= n; i++) {
    move(1, i, avg);
  }
  cout << ops.size() << "\n";
  for (auto x : ops) {
    cout << get<0>(x) << " " << get<1>(x) << " " << get<2>(x) << '\n';
  }
}
int main() {
  ios::sync_with_stdio(false), cin.tie(nullptr);
  int t = 1;
  cin >> t;
  while (t--) solve();
}
