#include <bits/stdc++.h>
using namespace std;
const double eps = 1e-9;
const int inf = 2000000000;
const long long infLL = 9000000000000000000;
template <typename first, typename second>
ostream& operator<<(ostream& os, const pair<first, second>& p) {
  return os << "(" << p.first << ", " << p.second << ")";
}
template <typename T>
ostream& operator<<(ostream& os, const vector<T>& v) {
  os << "{";
  for (auto it = v.begin(); it != v.end(); ++it) {
    if (it != v.begin()) os << ", ";
    os << *it;
  }
  return os << "}";
}
template <typename T>
ostream& operator<<(ostream& os, const set<T>& v) {
  os << "[";
  for (auto it = v.begin(); it != v.end(); ++it) {
    if (it != v.begin()) os << ",";
    os << *it;
  }
  return os << "]";
}
template <typename T>
ostream& operator<<(ostream& os, const multiset<T>& v) {
  os << "[";
  for (auto it = v.begin(); it != v.end(); ++it) {
    if (it != v.begin()) os << ", ";
    os << *it;
  }
  return os << "]";
}
template <typename first, typename second>
ostream& operator<<(ostream& os, const map<first, second>& v) {
  os << "[";
  for (auto it = v.begin(); it != v.end(); ++it) {
    if (it != v.begin()) os << ", ";
    os << it->first << " = " << it->second;
  }
  return os << "]";
}
void faltu() { cerr << '\n'; }
template <typename T>
void faltu(T a[], int n) {
  for (int i = 0; i < n; ++i) cerr << a[i] << ' ';
  cerr << '\n';
}
template <typename T, typename... hello>
void faltu(T arg, const hello&... rest) {
  cerr << arg << ' ';
  faltu(rest...);
}
const int mx = 2e5 + 5;
int t[mx];
int col[mx];
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  ;
  int q;
  cin >> q;
  while (q--) {
    int n;
    cin >> n;
    for (int i = 1; i <= n; ++i) cin >> t[i];
    int cur = t[1];
    int c = 1;
    for (int i = 1; i <= n; ++i) {
      if (cur == t[i])
        col[i] = c;
      else {
        if (c == 1)
          c = 2;
        else if (c == 2)
          c = 1;
        col[i] = c;
        cur = t[i];
      }
    }
    int ans = 0;
    if (t[1] != t[n] && col[1] == col[n]) {
      if (col[n - 1] == 1)
        col[n] = 2;
      else {
        bool ok = 0;
        for (int i = 2; i < n; ++i) {
          if (t[i] == t[i - 1]) {
            ok = 1;
            for (int j = i; j < n; ++j) {
              if (col[j] == 1)
                col[j] = 2;
              else
                col[j] = 1;
            }
            col[n] = 2;
            break;
          }
        }
        if (!ok) col[n] = 3;
      }
    }
    for (int i = 1; i <= n; ++i) ans = max(ans, col[i]);
    cout << ans << '\n';
    for (int i = 1; i <= n; ++i) cout << col[i] << " ";
    cout << '\n';
  }
}
