#include <iostream>
#include <vector>
#include <string>

using namespace std;

int arr[20], nofs = 0;

void gen(const vector<int> &mvc, vector<string> &res, int n, int i = 0)
{
    if (i == n) {
        int a, b;
        string s;
        int sumofa = 0, sumofb = 0;
        for(int j = 0; j < n; ++j) {
            if (arr[j] == 0) {
                s.push_back('A');
                sumofa += mvc[i];
            }
            else {
                s.push_back('B');
                sumofb += mvc[i];
            }
        }
        if (sumofa == sumofb) {
            res.push_back(s);
            ++nofs;
        }
    }
    else {
        arr[i] = 0;
        gen(mvc, res, n, i + 1);
        arr[i] = 1;
        gen(mvc, res, n, i + 1);
    }
}

int main()
{
    int n;
    vector<int> mvc; // store input sequence
    vector<string> res; // store result
    cin >> n;
    mvc.resize(n);
    res.resize(n);
    for (int i = 0; i < n; ++i) {
        res[i].resize(n);
        cin >> mvc[i];
    }
    gen(mvc, res, n);
    if (nofs > 0) {
        cout << nofs << endl;
        for (int i = 0; i < nofs; ++i) {
            for (int j = 0; j < n; ++j) {
                cout << res[i][j] << " ";
            }
            cout << endl;
        }
    }
    else cout << "khong chia duoc";
    return 0;
}