#include <iostream>
#include <cstring>
#include <algorithm>
#include <vector>
#include <map>
#include <array>
#include <set>
#include <cmath>
#include <iomanip>
#include <queue>
#include <unordered_map>
#include <chrono>
#include <stack>
#include <numeric>

#define x first

#define y second

#define int long long

using namespace std;

const int mod = 1e9 + 7;

typedef long long ll;
typedef pair<int, int> PII;

const int N = 2e5 + 10;

int da[10010], db[10010], n, m;
string s;

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    cin >> n >> m;

    for (int i = 1; i <= n; i++) {
        cin >> s;
        for (int j = 0; j < n; j++) {
            if (s[j] == '1')
                da[j + 1]++;
        }
    }

    for (int i = 1; i <= m; i++) {
        cin >> s;
        for (int j = 0; j < m; j++) {
            if (s[j] == '1')
                db[j + 1]++;
        }
    }
    bool fa = false, fb = false;
    for (int i = 1; i <= n; i++) {
        if (da[i] != n - 1)
            fa = true;
    }
    for (int i = 1; i <= m; i++) {
        if (db[i] != m - 1)
            fb = true;
    }

    if (!fa && !fb) {
        cout << n << "\n";
    }
    if (!fa && fb) {
        cout << 2 << "\n";
    }
    if (fa) {
        cout << 1 << "\n";
    }
    return 0;
}