#include <algorithm>
#include <iostream>
using namespace std;
typedef long long ll;

int main()
{
    int n;
    ll k;
    cin >> n >> k;
    n *= 2;
    string s[505];
    for (int i = 0; i < n; i++)
    {
        cin >> s[i];
    }
    int c[505][505];
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < n; j++)
        {
            cin >> c[i][j];
        }
    }
    int x = 0;
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < n; j++)
        {
            x += (s[i][j] == '#');
        }
    }
    int d[250005], e[130000];
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < n; j++)
        {
            d[i * n + j] = c[i][j];
        }
    }
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < n / 2; j++)
        {
            e[i * n / 2 + j] = c[i][j] + c[i][n - 1 - j];
        }
    }
    sort(d, d + n * n, greater<int>());
    sort(e, e + n * n / 2, greater<int>());
    ll ans = 0;
    for (int i = 0; i < x; i++)
    {
        ans += d[i];
    }
    if (x % 2 == 0)
    {
        ll s = k;
        for (int i = 0; i < x / 2; i++)
        {
            s += e[i];
        }
        ans = max(ans, s);
    }
    cout << ans << endl;
}