// 基本テンプレート
 
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <string>
#include <cstring>
#include <deque>
#include <list>
#include <queue>
#include <stack>
#include <vector>
#include <utility>
#include <algorithm>
#include <map>
#include <set>
#include <complex>
#include <cmath>
#include <limits>
#include <cfloat>
#include <climits>
#include <ctime>
#include <cassert>
#include <numeric>
#include <fstream>
#include <functional>
using namespace std;
 
#define rep(i,a,n) for(int (i)=(a); (i)<(n); (i)++)
#define repq(i,a,n) for(int (i)=(a); (i)<=(n); (i)++)
#define repr(i,a,n) for(int (i)=(a); (i)>=(n); (i)--)
#define debug(...) fprintf(stderr, __VA_ARGS__)
#define int long long int
 
template<typename T> void chmax(T &a, T b) {a = max(a, b);}
template<typename T> void chmin(T &a, T b) {a = min(a, b);}
template<typename T> void chadd(T &a, T b) {a = a + b;}
 
typedef pair<int, int> pii;
typedef long long ll;
 
int dx[] = {0, 0, 1, -1, 1, 1};
int dy[] = {1, -1, 0, 0, 1, -1};
const ll INF = 1001001001001001LL;
const ll MOD = 1000000007LL;

int N, board[300][300];
 
int solve(int row, int col) {
    int res = 0;
    for(int k=0; k<6; k++) {
        int x = row, y = col, cons = 0;
        while(x >= 0 and x < N and y >= 0 and y < N) {
            if(board[x][y] > 0) cons++;
            else chmax(res, cons), cons = 0;
            x += dx[k], y += dy[k];
        }
        chmax(res, cons);
    }
    return res;
}

signed main() {
    while(cin >> N, N) {
        for(int i=0; i<N; i++) {
            for(int j=0; j<N; j++) {
                char c; cin >> c;
                board[i][j] = c - '0';
            }
        }

        int ans = 0;
        for(int i=0; i<N; i++) {
            chmax(ans, solve(i, 0));
            chmax(ans, solve(0, i));
            chmax(ans, solve(N-1, i));
            chmax(ans, solve(i, N-1));
        }
        cout << ans << endl;
    }
    return 0;
}
