#include <bits/stdc++.h>
using namespace std;
template <typename A>
using VE = vector<A>;
template <typename A>
using USET = unordered_set<A>;
template <typename A>
using HEAP = priority_queue<A>;
template <typename A, typename B>
using PA = pair<A, B>;
template <typename A, typename B>
using UMAP = unordered_map<A, B>;
template <typename A>
using RHEAP = priority_queue<A, vector<A>, greater<A> >;
template <typename A>
A MAX(const A &a) {
  return a;
}
template <typename A>
A MIN(const A &a) {
  return a;
}
template <typename A>
A MAX(const A *a, const A *b) {
  return *max_element(a, b);
}
template <typename A>
A MIN(const A *a, const A *b) {
  return *min_element(a, b);
}
template <typename A, typename... B>
A MAX(const A &a, const B &...b) {
  return max(a, MAX(b...));
}
template <typename A, typename... B>
A MIN(const A &a, const B &...b) {
  return min(a, MIN(b...));
}
template <typename A, typename B = typename std::iterator_traits<A>::value_type>
B MAX(A a, A b) {
  return *max_element(a, b);
}
template <typename A, typename B = typename std::iterator_traits<A>::value_type>
B MIN(A a, A b) {
  return *min_element(a, b);
}
mt19937 rng(
    (unsigned int)chrono::steady_clock::now().time_since_epoch().count());
const int N = 100010, M = 1010;
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  cout << fixed << setprecision(10);
  int T;
  cin >> T;
  while (T--) {
    int n;
    cin >> n;
    int idx = 0;
    map<int, int> mp;
    vector<int> a(n);
    for (auto &u : a) {
      cin >> u;
      if (!mp.count(u)) mp[u] = ++idx;
      u = mp[u];
    }
    int p = -1;
    for (int i = 0; i < n; i++)
      if (a[i] == a[(i + 1) % n]) {
        p = i;
        break;
      }
    vector<int> c(n);
    if (p == -1) {
      for (int i = 0, j = 1; i + 1 < n; i += 2) {
        c[i] = j;
        j = 3 - j;
        c[i + 1] = j;
        j = 3 - j;
      }
      if (c.back() == 0) {
        if (c[n - 2] != c[0])
          c.back() = 3;
        else
          c.back() = 3 - c[0];
      }
    } else {
      rotate(a.begin(), a.begin() + p + 1, a.end());
      c[0] = 1;
      for (int i = 1; i < n; i++)
        if (a[i] != a[i - 1])
          c[i] = 3 - c[i - 1];
        else
          c[i] = 1;
    }
    cout << MAX(c.begin(), c.end()) << '\n';
    int j;
    if (p == -1)
      j = 0;
    else
      j = n - p - 1;
    for (int i = 0; i < n; i++, j++) cout << c[j % n] << ' ';
    cout << '\n';
  }
  return 0;
}
