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

int main() {
	int N;
	cin >> N;
	vector<string> s(N);
	for (int i = 0; i < N; i++)
	{
		cin >> s[i];
	}

	vector<int> a, b;
	vector<int> win(N);
	for (int i = 0; i < N; i++)
	{
		for (int j = 0; j < i; j++)
		{
			if (s[i][j] == '-'){
				a.push_back(i);
				b.push_back(j);
			}
			else if (s[i][j] == 'o'){
				win[i]++;
			}
			else{
				win[j]++;
			}
		}
	}

	int ans = N;
	for (int i = 0; i < (1 << a.size()); i++)
	{
		vector<int> wintemp(win);
		for (int j = 0; j < a.size(); j++)
		{
			if ((i >> j) % 2) wintemp[a[j]]++;
			else wintemp[b[j]]++;
		}
		for (int i = 0; i < N; i++)
		{
			wintemp[i] = wintemp[i] * N + i;
		}
		sort(wintemp.begin(), wintemp.end());
		reverse(wintemp.begin(), wintemp.end());

		int place = 0;
		int prepoint = -1;
		for (int i = 0; i < N; i++)
		{
			int winnum = wintemp[i] / N;
			int team = wintemp[i] % N;
			if (prepoint != winnum){
				prepoint = winnum;
				place++;
			}
			if (team == 0) ans = min(place, ans);
		}
	}
	cout << ans << endl;
}