#include <stdio.h>
#include <vector>
using namespace std;

#define maxN    15

int N;
char A[maxN][maxN];
int v[maxN], a[maxN], Sol;
vector <int> x[maxN];

void verif () {
    int i, j, ok;
    vector <int> :: iterator k, l;

    for (i = 1; i <= N; ++ i)
        x[i].clear();

    for (i = 1; i <= N; ++ i)
        x[v[i]].push_back(i);

    for (i = 1; x[i].size() && i <= N; ++ i)
        for (j = 1; x[j].size() && i <= N; ++ j)
            if (i != j) {
                ok = false;
                for (k = x[i].begin(); k != x[i].end() && !ok; ++ k)
                    for (l = x[j].begin(); l != x[j].end() && !ok; ++ l)
                        if (A[*k][*l])
                             ok = true;
                if (!ok)
                    return;
            }
    ++ Sol;
}

void back (int k, int n) {
    if (k == n + 1) {
        verif();
        return ;
    }

    for (int i = 1; i <= n; ++ i)
        if (a[i - 1]) {
            a[i] ++;
            v[k] = i;
            back(k + 1, n);
            a[i] --;
        }
}

int main () {
    int i;

    freopen("copii.in", "r", stdin);
    freopen("copii.out", "w", stdout);

    scanf("%d", &N);

    for (i = 1; i <= N; ++ i)
        gets(A[i] + 1);

    a[0] = 1;
    back(1, N);
    printf("%d\n", Sol);
}