#include <bits/stdc++.h>
using namespace std;

#ifdef _RUTHEN
#include <debug.hpp>
#else
#define show(...) true
#endif

using ll = long long;
#define rep(i, n) for (int i = 0; i < (n); i++)
template <class T> using V = vector<T>;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    int N;
    cin >> N;
    ll K;
    cin >> K;
    int N2 = N * 2;
    V<string> S(N2);
    rep(i, N2) cin >> S[i];
    V<V<ll>> C(N2, V<ll>(N2));
    rep(i, N2) rep(j, N2) cin >> C[i][j];
    V<ll> B;
    rep(i, N2) rep(j, N2) B.push_back(C[i][j]);
    sort(B.rbegin(), B.rend());
    show(B);
    int cnt = 0;
    rep(i, N2) rep(j, N2) cnt += S[i][j] == '#';
    ll ans = accumulate(B.begin(), B.begin() + cnt, 0LL);
    show(ans);
    map<int, ll> dp;
    dp[0] = 0;
    rep(i, N2) {
        rep(j, N) {
            map<int, ll> np;
            // #
            int c1 = 0, c2 = 0;
            if (S[i][j] == '.') c1++;
            if (S[i][N2 - 1 - j] == '.') c1++;
            // .
            if (S[i][j] == '#') c2--;
            if (S[i][N2 - 1 - j] == '#') c2--;
            for (auto &[k, v] : dp) {
                if (np.count(k + c1)) {
                    np[k + c1] = max(np[k + c1], v + C[i][j] + C[i][N2 - 1 - j]);
                } else {
                    np[k + c1] = v + C[i][j] + C[i][N2 - 1 - j];
                }
                if (np.count(k + c2)) {
                    np[k + c2] = max(np[k + c2], v);
                } else {
                    np[k + c2] = v;
                }
            }
            swap(np, dp);
            show(dp);
        }
    }
    if (dp.count(0)) ans = max(ans, dp[0] + K);
    cout << ans << '\n';
    return 0;
}