#include <bits/stdc++.h>
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/tree_policy.hpp>

#define fa ios_base::sync_with_stdio(false);cin.tie(nullptr);cout.tie(0);
typedef long long ll;
typedef long double ld;
typedef double d;
typedef unsigned long long ull;
#define all(v) ((v).begin()),((v).end())
#define rall(v) ((v).rbegin()),((v).rend())
using namespace std;
using namespace __gnu_pbds;
template<typename T>
using orderedset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;


template<typename T = ll>
istream &operator>>(istream &in, vector<T> &v) {
    for (auto &x: v) in >> x;
    return in;
}

template<typename T = ll>
ostream &operator<<(ostream &out, const vector<T> &v) {
    for (const T &x: v) out << x << ' ';
    return out;
}

#include <bits/stdc++.h>
using namespace std;

// A sample function whose time taken to
// be measured

const int N = 100 + 5;


int n, m;
int arr[N][N];
int vis[N][N];
int vis1[N][N];
int dx[] = {1, -1, 0, 0}, dy[] = {0, 0, 1, -1};


bool valid(int x, int y) {
    return x >= 0 && x < n && y >= 0 && y < m;
}

void dfs1(int nodeX, int nodeY) {

    vis1[nodeX][nodeY] = 1;

    for (int i = 0; i < 4; i++) {
        int nxtX = nodeX + dx[i], nxtY = nodeY + dy[i];
        if (valid(nxtX, nxtY) && !vis1[nxtX][nxtY]) {
            dfs1(nxtX, nxtY);
        }
    }

}

bool conn() {

    int cnt = 0;

    for (int i = 0; i <= n; i++) {
        for (int j = 0; j <= m; j++) {
            vis1[i][j] = vis[i][j];
        }
    }

    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) {
            if (!vis1[i][j]) {
                dfs1(i, j);
                cnt++;
            }
        }
    }

    return cnt == 1;

}
ull mn=18446744073709551615ull;
void multi(){
    ull a=1,b=1;
    int cnt1=0,cnt2=0;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) {
if(vis[i][j])
    a*=arr[i][j],cnt1++;
else
    b*=arr[i][j],cnt2++;
        }
        }
if(cnt2==0||cnt1==0)
    return;
   mn=min( max(a,b)-min(a,b),mn);
}
void dfs(int nodeX, int nodeY) {

    vis[nodeX][nodeY] = 1;
    if(conn())
    multi();
    for (int i = 0; i < 4; i++) {
        int nxtX = nodeX + dx[i], nxtY = nodeY + dy[i];
        if (valid(nxtX, nxtY) &&   !vis[nxtX][nxtY]) {
//            vis[nxtX][nxtY] = 1;
            dfs(nxtX, nxtY);
   //         vis[nxtX][nxtX] = 0;
        }
    }

}

void clear(){
    for (int i = 0; i <= n; i++) {
        for (int j = 0; j <= m; j++) {
            vis[i][j] = 0;
        }
    }
}
signed main() {
//#ifndef ONLINE_JUDGE
//    freopen("i.txt", "r", stdin);
//    freopen("o.txt", "w", stdout);
//#endif
    fa

    ll T = 1, k;
    // cin >> T;

    while (T--) {




        time_t start, end;


        time(&start);
        cin >> n >> m;
int cnt=0;
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < m; j++) {
                cin >> arr[i][j];
                if(arr[i][j]==2)
                    cnt++;
            }
        }
if(cnt==64)
{
    cout<<0;
    return 0;
}
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < m; j++) {
                clear();
                dfs(i, j);
            }
        }

        cout<<mn;
        time(&end);


//        auto time_taken = double(end - start);
//        cout << "Time taken by program is : " << fixed
//             << time_taken << setprecision(5);
//        cout << " sec " << endl;

    }


}