#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
#define rep(i, n) for(int i=0;i<(n);++i)
#define rep1(i, n) for(int i=1;i<=(n);i++)
#define ll long long
using mint = modint998244353;
using P = pair<ll,ll>;
using lb = long double;
using T = tuple<ll, ll, ll>;
#ifdef LOCAL
#  include <debug_print.hpp>
#  define dbg(...) debug_print::multi_print(#__VA_ARGS__, __VA_ARGS__)
#else
#  define dbg(...) (static_cast<void>(0))
#endif

int main()
{
    int n;
    cin >> n;
    vector<string> s(n);
    rep(i,n) cin >> s[i];
    int ans = 0;
    rep(i,n) {
        int cnt = 0;
        int b = 0;
        rep(j,n) {
            if(s[i][j]=='A') cnt++;
            else if(s[i][j]=='B') b++;
        }
        if(cnt==n-1 && b == 0) ans++;
    }
    rep(j,n){
        int cnt = 0;
        int b = 0;
        rep(i,n) {
            if(s[i][j]=='A') cnt++;
            else if(s[i][j]=='B') b++;
        }
        if(cnt==n-1 && b == 0) ans++;
    }
    int cnt = 0;
    int b = 0;
    rep(i,n) {
        if(s[i][i]=='A') cnt++;
        else if(s[i][i]=='B') b++;
    }
    if(cnt==n-1 && b==0) ans++;
    cnt = 0;
    b = 0;
    rep(i,n) {
        if(s[i][n-i-1]=='A') cnt++;
        else if(s[i][n-i-1]=='B') b++;
    }
    if(cnt==n-1 && b==0) ans++;
    cout << ans << endl;
    return 0;
}