#include <algorithm>
#include <cmath>
#include <cstdio>
#include <cstring>
#include <deque>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <utility>
#include <vector>

#define p(s) cout<<(s)<<endl
#define REP(i,n,N) for(int i=n;i<N;i++)
#define RREP(i,n,N) for(int i=N-1;i>=n;i--)
#define CK(n,a,b) ((a)<=(n)&&(n)<(b))
#define F first
#define S second
typedef long long int ll;
using namespace std;
const ll inf=1e9+7;

int N;
string s[10];
vector<pair<int, int>> vp;
int main(){
    cin>>N;
    int ans=inf;
    REP(i,0,N){
        cin>>s[i];
    }
    vector<int> win(N,0);
    REP(i,0,N){
        REP(j,i+1,N){
            if(s[i][j]=='-')vp.push_back({i, j});
            else if(s[i][j]=='o') win[i]++;
            else win[j]++;
        }
    }

    REP(mask, 0, 1 << (vp.size())) {
        vector<int> wins = win;
        REP(i, 0, vp.size()) {
            if (mask & (1 << i)) {
                wins[vp[i].F]++;
            } else {
                wins[vp[i].S]++;
            }
        }
        int k = wins[0];
        sort(wins.begin(), wins.end());
        wins.erase(unique(wins.begin(), wins.end()), wins.end());
        reverse(wins.begin(), wins.end());
        REP(i, 0, N) {
            if (wins[i] == k) {
                ans = min(ans, i + 1);
                break;
            }
        }
    }

    p(ans);

    return 0;
}