#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
// using mint = modint1000000007;
// const int mod = 1000000007;
// using mint = modint998244353;
// const int mod = 998244353;
// const int INF = 1e9;
// const long long LINF = 1e18;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep2(i, l, r) for (int i = (l); i < (r); ++i)
#define rrep(i, n) for (int i = (n)-1; i >= 0; --i)
#define rrep2(i, l, r) for (int i = (r)-1; i >= (l); --i)
#define all(x) (x).begin(), (x).end()
#define allR(x) (x).rbegin(), (x).rend()
#define P pair<int, int>
template<typename A, typename B> inline bool chmax(A &a, const B &b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A &a, const B &b) { if (a > b) { a = b; return true; } return false; }

int main() {
	std::ios::sync_with_stdio(false);
	std::cin.tie(nullptr);
	int n; cin >> n;
	vector<string>s(n);
	rep(i, n)cin >> s[i];
	vector<P>x, y;
	rep(i, n) {
		rep(j, n) {
			if (s[i][j] == '#')x.push_back({ i,j });
		}
		rep(j, n) {
			if (s[i][j + n] != '#')y.push_back({ i,j + n });
		}
	}
	//cout << x.size() << endl;
	long long ans = 0;
	{
		long long a = 0, b = 0;
		for (auto[x, y] : x) {
			a += y;
		}
		for (auto[x, y] : y) {
			b += y;
		}
		ans += b - a;
		//cout << ans << endl;
	}
	{
		vector<int>a, b;
		for (auto[x, y] : x) {
			a.push_back(x);
		}
		for (auto[x, y] : y) {
			b.push_back(x);
		}
		sort(all(a));
		sort(all(b));
		rep(i, a.size())ans += abs(a[i] - b[i]);
	}
	cout << ans << endl;
	//int sz = x.size() + y.size();
	//int st = sz;
	//int ed = st + 1;

	return 0;
}