// #define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
using ll = long long;
using vi = vector<int>;
using vvi = vector<vector<int>>;
using pii = pair<int, int>;
#define rep(i, n) for (int i = 0; i < (int)(n); ++i)
#define repr(i, n) for (int i = (int)(n - 1); i >= 0; --i)

int main() {
    int n;
    ll K;
    cin >> n >> K;
    n *= 2;
    int cnt = 0;
    rep(i, n) rep(j, n) {
        char ch;
        cin >> ch;
        if (ch == '#') cnt++;
    }
    vvi c(n, vi(n));
    rep(i, n) rep(j, n) cin >> c[i][j];

    ll ret = 0;
    vi s;
    rep(i, n) rep(j, n) s.push_back(c[i][j]);
    sort(s.begin(), s.end(), greater<int>());
    rep(k, cnt) ret += s[k];
    if (~cnt & 1) {
        vi t;
        rep(i, n) rep(j, n / 2) t.push_back(c[i][j] + c[i][n - 1 - j]);
        sort(t.begin(), t.end(), greater<int>());
        ll tmp = K;
        rep(k, cnt / 2) tmp += t[k];
        ret = max(ret, tmp);
    }
    cout << ret << endl;
    return 0;
}