#include <bits/stdc++.h>
using namespace std;
long long int power(long long int a, long long int b) {
  long long int res = 1;
  a %= 1000000007;
  assert(b >= 0);
  for (; b; b >>= 1) {
    if (b & 1) res = res * a % 1000000007;
    a = a * a % 1000000007;
  }
  return res;
}
long long int modInverse(long long int a) { return power(a, 1000000007 - 2); }
const int N = 500023;
bool compare(long long int x, long long int y) { return x > y; }
void solve() {
  vector<int> primes = {
      2,   3,   5,   7,   11,  13,  17,  19,  23,  29,  31,  37,  41,  43,
      47,  53,  59,  61,  67,  71,  73,  79,  83,  89,  97,  101, 103, 107,
      109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181,
      191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263,
      269, 271, 277, 281, 283, 293, 307, 311, 313, 317, 331, 337, 347, 349,
      353, 359, 367, 373, 379, 383, 389, 397, 401, 409, 419, 421, 431, 433,
      439, 443, 449, 457, 461, 463, 467, 479, 487, 491, 499, 503, 509, 521,
      523, 541, 547, 557, 563, 569, 571, 577, 587, 593, 599, 601, 607, 613,
      617, 619, 631, 641, 643, 647, 653, 659, 661, 673, 677, 683, 691, 701,
      709, 719, 727, 733, 739, 743, 751, 757, 761, 769, 773, 787, 797, 809,
      811, 821, 823, 827, 829, 839, 853, 857, 859, 863, 877, 881, 883, 887,
      907, 911, 919, 929, 937, 941, 947, 953, 967, 971, 977, 983, 991, 997};
  int n, value, nocolor = 1, colored = 0;
  cin >> n;
  vector<pair<int, int>> color;
  for (int i = 0; i < n; i++) {
    cin >> value;
    color.push_back(make_pair(value, 0));
  }
  for (int i = 0; i < primes.size(); i++) {
    for (int j = 0; j < n; j++) {
      if ((color[j].first % primes[i] == 0) && (color[j].second == 0)) {
        color[j].second = nocolor;
        colored = 1;
      }
    }
    if (colored) {
      nocolor++;
    }
    colored = 0;
  }
  cout << nocolor - 1 << endl;
  for (int i = 0; i < n; i++) {
    cout << color[i].second << " ";
  }
  cout << endl;
  return;
}
int main() {
  {
    ios ::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
  };
  int T;
  cin >> T;
  int t = 0;
  while (t++ < T) {
    solve();
  }
  cerr << "Time : " << 1000 * ((double)clock()) / (double)CLOCKS_PER_SEC
       << "ms\n";
}
