#include<iostream>
#include<string>
#include<cstdio>
#include<vector>
#include<cmath>
#include<algorithm>
#include<functional>
#include<iomanip>
#include<queue>
#include<ciso646>
#include<random>
#include<map>
#include<set>
#include<complex>
#include<bitset>
#include<stack>
#include<unordered_map>
using namespace std;
typedef long long ll;
typedef unsigned int ui;
const ll mod = (ll)(1e+9) + 7;
const ll INF = (ll)1000000007 * 1000000007;
typedef pair<int, int> P;
#define stop char nyaa;cin>>nyaa;
#define rep(i,n) for(int i=0;i<n;i++)
#define per(i,n) for(int i=n-1;i>=0;i--)
#define Rep(i,sta,n) for(int i=sta;i<n;i++)
#define rep1(i,n) for(int i=1;i<=n;i++)
#define per1(i,n) for(int i=n;i>=1;i--)
#define Rep1(i,sta,n) for(int i=sta;i<=n;i++)
typedef long double ld;
typedef complex<ld> Point;
const ld eps = 1e-8;
const ld pi = acos(-1.0);
typedef pair<ll, ll> LP;
typedef pair<ld, ld> LDP;
char w[6][6];
bool comp(P x, P y) {
	if (x.first != y.first)return x.first > y.first;
	return x.second < y.second;
}
int main() {
	int n; cin >> n;
	int m = n * (n - 1) / 2;
	rep(i, n) {
		rep(j, n) {
			cin >> w[i][j];
		}
	}
	int out = 10;
	rep(k, (1 << m)) {
		int c[6] = {};
		int h = 0;
		rep(i, n) {
			Rep(j, i + 1, n) {
				if (w[i][j] == 'o' || (w[i][j] == '-' && (k&(1 << h)))) {
					c[i]++;
				}
				else c[j]++;
				h++;
			}
		}
		vector<P> v;
		rep(i, n) {
			v.push_back({ c[i],i });
		}
		sort(v.begin(), v.end(),comp);
		int r = 0;
		int hosei = 0;
		rep(i, n) {
			if (i >= n - hosei)break;
			if (i > 0 && v[i].first == v[i - 1].first) {
				i--; v.erase(v.begin() + i); hosei++;
			}
			if (!v[i].second)r = i + 1;
			//cout << v[i].first << " " << v[i].second << endl;
		}
		//cout << endl;
		out = min(out, r);
	}
	cout << out << endl;
	return 0;
}