#include <bits/stdc++.h>
using namespace std;

int main() {
    int n;
    cin >> n;
    vector<string> g(n);
    for (int i = 0; i < n; i++) cin >> g[i];
    for (int j = 0; j < n; j++) {
        if (g[0][j] == '-') {
            g[0][j] = 'o';
            g[j][0] = 'x';
        }
    }
    int win_0 = 0;
    for (int i = 0; i < n; i++) {
        if (g[0][i] == 'o') win_0++;
    }

    vector<pair<int, int>> un;
    for (int i = 1; i < n; i++) {
        for (int j = i + 1; j < n; j++) {
            if (g[i][j] == '-') { un.push_back({i, j}); }
        }
    }

    int k = (int)un.size();
    int ans = 100;
    for (int bit = 0; bit < (1 << k); k++) {
        vector<string> g2 = g;
        for (int i = 0; i < k; i++) {
            if (bit & (1 << i)) {
                g2[un[i].first][un[i].second] = 'o';
                g2[un[i].second][un[i].first] = 'x';
            }
        }
        int rank = 1;
        for (int i = 1; i < n; i++) {
            int win_i = 0;
            for (int j = 0; j < n; j++) {
                if (g2[i][j] == 'o') win_i++;
            }
            if (win_i > win_0) rank++;
        }
        ans = min(ans, rank);
    }
    cout << ans << endl;
    return 0;
}