#include <bits/stdc++.h>
#define int long long
using namespace std;
main() {
	int t;
	cin >> t;
	while(t--) {
		int n;
		cin >> n;
		int a[n];
		for(int i = 0; i < n; i++) {
			cin >> a[i];
		}
		int col = 1;
		int ans[n] = {0};
		int rest = n;
		for(int i = 2; rest > 0; i++) {
			bool ok = 0;
			bool ch = 0;
			for(int j = 0; j < n; j++) {
				if(!ans[j] && a[j] % i == 0) {
					ch = 1;
					rest--;
					ans[j] = col;
        }
        if(rest == 0) {
        	ok = 1;
        	break;
        }
			}
			if(ok) break;

			if(ch) col++;
	 	}
	 	cout << col << endl;
	 	for(int i = 0; i < n; i++) {
	 		cout << ans[i] << " ";
	 	}
	 	puts("");
	}
}