#include #include #include #include #include #include

using namespace std;

int n; vector brightness; vector octagons; vector<vector> rotated; int min_sum = INT_MAX;

void backtrack(int pos, char req_color, int current_sum, const vector& perm, const vector& used) { if (pos == n) { if (req_color == rotated[perm[0]][0][6]) { if (current_sum < min_sum) { min_sum = current_sum; } } return; } int oct_idx = perm[pos]; for (const string& rot : rotated[oct_idx]) { if (rot[6] == req_color) { char new_req_color = rot[2]; int new_sum = current_sum + brightness[rot[2] - 'A']; if (new_sum < min_sum) { backtrack(pos + 1, new_req_color, new_sum, perm, used); } } } }

void solve() { while (true) { cin >> n; if (n == 0) break; brightness.resize(8); for (int i = 0; i < 8; ++i) { cin >> brightness[i]; } octagons.resize(n); for (int i = 0; i < n; ++i) { cin >> octagons[i]; }

    rotated.clear();
    rotated.resize(n);
    for (int i = 0; i < n; ++i) {
        string oct = octagons[i];
        for (int j = 0; j < 8; ++j) {
            rotated[i].push_back(oct.substr(j) + oct.substr(0, j));
        }
    }
    
    min_sum = INT_MAX;
    vector<int> perm(n);
    for (int i = 0; i < n; ++i) {
        perm[i] = i;
    }
    
    do {
        string first_oct = rotated[perm[0]][0];
        char required_color = first_oct[2];
        int current_sum = brightness[first_oct[6] - 'A'];
        vector<bool> used(n, false);
        used[perm[0]] = true;
        backtrack(1, required_color, current_sum, perm, used);
    } while (next_permutation(perm.begin(), perm.end()));
    
    if (min_sum != INT_MAX) {
        cout << min_sum << endl;
    } else {
        cout << "impossible" << endl;
    }
}

}

int main() { solve(); return 0; }