#include <bits/stdc++.h>
using namespace std;
const long long N = 2e5 + 5;
const long long inf = 199999999999999999;
const long long mod = 1e9 + 7;
void read() {
  freopen("lifeguards.in", "r", stdin);
  freopen("lifeguards.out", "w", stdout);
}
void solve() {
  int coloured[N] = {}, pp[N] = {}, mx = 0, mx1 = 0, attribute = 0, cur = 0;
  long long n;
  cin >> n;
  vector<long long> v(n);
  for (auto &i : v) {
    cin >> i;
    if (i == cur) attribute = 1;
    cur = i;
  }
  if (v[0] == v[n - 1]) attribute = 1;
  if (is_sorted(v.begin(), v.end()) && v[0] == v[n - 1]) {
    cout << "1\n";
    for (int i = 0; i < n; ++i) {
      cout << "1 ";
    }
    return;
  }
  if (n & 1 ^ 1) {
    cout << "2\n";
    for (int i = 0; i < n; ++i) {
      if (i & 1)
        cout << "1 ";
      else
        cout << "2 ";
    }
    return;
  } else {
    if (attribute) {
      cout << "2\n";
      long long op = 1, borely = 1;
      cur = 2;
      for (int i = 0; i < n; ++i) {
        if (v[i] == v[i - 1] && op) {
          if (cur == 2)
            cout << "2 ", cur = 2;
          else
            cout << "1 ", cur = 1;
          op ^= 1;
          continue;
        }
        if (cur == 2)
          cout << "1 ", cur = 1;
        else
          cout << "2 ", cur = 2;
      }
    } else {
      cout << "3\n";
      for (int i = 0; i < n - 1; ++i) {
        if (i & 1)
          cout << "1 ";
        else
          cout << "2 ";
      }
      cout << 3;
    }
  }
}
int32_t main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  long long T = 1;
  cin >> T;
  while (T--) {
    solve();
    cout << '\n';
  }
  cerr << "\nTime elapsed:" << 1.0 * clock() / CLOCKS_PER_SEC << " s.\n";
}
