#include "bits/stdc++.h"
using namespace std;
#define int long long
#define FOR(i, a, b) for(int i=(a);i<(b);i++)
#define RFOR(i, a, b) for(int i=(b-1);i>=(a);i--)
#define REP(i, n) for(int i=0; i<(n); i++)
#define RREP(i, n) for(int i=(n-1); i>=0; i--)
#define ALL(a) (a).begin(),(a).end()
#define UNIQUE_SORT(l) sort(ALL(l)); l.erase(unique(ALL(l)), l.end());
#define CONTAIN(a, b) find(ALL(a), (b)) != (a).end()
#define array2(type, x, y) array<array<type, y>, x>
#define vector2(type) vector<vector<type> >
#define out(...) printf(__VA_ARGS__)

int dx[] = {0,1,1,0,-1,-1,-1, 0, 1};
int dy[] = {0,0,1,1, 1, 0,-1,-1,-1};

void solve();
signed main()
{
#if DEBUG
    std::ifstream in("input.txt");
    std::cin.rdbuf(in.rdbuf());
#endif
    cin.tie(0);
    ios::sync_with_stdio(false);
    solve();
    return 0;
}

/*================================*/

int N,M,Q;
int A[10][10], T[10][10];
int REV;

void print(int T[][10]) {
    REP(m,M) {
        REP(n,N) {
            cout << T[m+1][n+1];
        }
        cout << endl;
    }
    cout << "-----" << endl;
}

void reverse(int T[][10], int m, int n) {
    REV++;
    REP(i,9) {
        int nm = m + dx[i];
        int nn = n + dy[i];
        T[nm][nn] = !T[nm][nn];
    }
//    out("%lld, %lld\n", m, n);
//    print(T);
}

bool ok(int T[][10]) {
    REP(m,M)REP(n,N) if (T[m+1][n+1]) return false;
    return true;
}

void solve() {
    cin>>M>>N;
    REP(m,M)REP(n,N) cin>>A[m+1][n+1];
    
    int ans = LONG_LONG_MAX;
    REP(i,1<<N)REP(k,1<<(M-1)) {
        REP(m,M+2)REP(n,N+2)T[m][n]=A[m][n];
//        cout << bitset<4>(i) << " " << bitset<3>(k) << endl;
//        print(T);
        REV=0;
        REP(j,N) {
            if (i&(1<<j)) reverse(T, 1, j+1);
        }
        REP(j,M-1) {
            if (k&(1<<j)) reverse(T, j+2, 1);
        }
        REP(m,M-1)REP(n,N-1) {
            if (T[m+1][n+1]) reverse(T, m+2, n+2);
        }
        if (ok(T)) {
//            out("%lld\n", REV);
            ans = min(ans, REV);
        }
    }
    
    if (ans > 100) {
        cout << "Impossible" << endl;
    } else {
        cout << ans << endl;
    }
}