#include <bits/stdc++.h>
using namespace std;
#define all(v) (v).begin(), (v).end()
using ll = long long;
using ld = long double;
using pint = pair<int, int>;
using pll = pair<ll, ll>;

int main() {
    int N; cin >> N;
    vector<string> S(N);
    for (int i = 0; i < N; i++) cin >> S[i];
    int ans = 0;
    for (int i = 0; i < N; i++) {
        ans += (count(all(S[i]), 'A') == N-1) && (count(all(S[i]), 'B') == 0);
        int cnt = 0;
        for (int j = 0; j < N; j++) {
            cnt += (S[j][i] == 'A');
            if (S[j][i] == 'B') cnt = -1e9;
        }
        ans += (cnt == N-1);
    }
    int cnt1 = 0, cnt2 = 0;
    for (int i = 0; i < N; i++) {
        cnt1 += (S[i][i] == 'A');
        cnt2 += (S[i][N-1-i] == 'A');
        if (S[i][i] == 'B') cnt1 = -1e9;
        if (S[i][N-1-i] == 'B') cnt2 = -1e9;
    }
    ans += (cnt1 == N-1);
    ans += (cnt2 == N-1);
    cout << ans << endl;
}