#include <algorithm>
#include <cstdio>
#include <cstdlib>
#include <cctype>
#include <cmath>
#include <iostream>
#include <queue>
#include <list>
#include <stack>
#include <map>
#include <numeric>
#include <set>
#include <sstream>
#include <string>
#include <vector>
using namespace std;
#define REP(i,a,n) for(int i=(a); i<(int)(n); i++)
#define rep(i,n) REP(i,0,n)
#define FOR(it,c) for(__typeof((c).begin()) it=(c).begin(); it!=(c).end(); ++it)
#define ALLOF(c) (c).begin(), (c).end()
typedef long long ll;

struct ST {
  int m;
  vector<int> v;
  ST(int n):v(n,0){}
};

ll c;

ll calc(const ST& a, const ST& b){
  ll ret = 0;
  int N = a.v.size();
  int i=0, j=0;
  while(i<N && j<N){
    if(ret + max(N-i, N-j) < c) return -1;
    if(a.v[i] == b.v[j]){
      ret++;
      i++;
      j++;
    }
    else if(a.v[i] < b.v[j]){
      i++;
    }
    else if(a.v[i] > b.v[j]){
      j++;
    }
  }
  
  return ret;
}

int main(){
  ios::sync_with_stdio(false);
  
  int N, M;
  cin >> N >> M;
  vector< vector<ST> > w;
  
  rep(i,M){
    vector<ST> v;
    vector< vector<int> > card(N, vector<int>(N, 0));
    rep(j,N){
      rep(k,N){
        cin >> card[j][k];
      }
    }

    rep(j,N){
      ST st(N);
      st.m = i;
      rep(k,N) st.v[k] = card[j][k];
      sort(ALLOF(st.v));
      v.push_back(st);
    }
    rep(k,N){
      ST st(N);
      st.m = i;
      rep(j,N) st.v[j] = card[j][k];
      sort(ALLOF(st.v));
      v.push_back(st);
    }
    {
      ST st1(N), st2(N);
      st1.m = i;
      st2.m = i;
      rep(j,N){
        st1.v[j] = card[j][j];
        st2.v[j] = card[j][N-1-j];
      }
      sort(ALLOF(st1.v));
      sort(ALLOF(st2.v));
      v.push_back(st1);
      v.push_back(st2);
    }
    w.push_back(v);
  }

  c = 0;
  rep(i,w.size()){
    rep(ii,w[i].size()){
      REP(j,i+1,w.size()){
        rep(jj,w[j].size()){
          c = max(c, calc(w[i][ii], w[j][jj]));
        }
      }
    }
  }

  cout << 2LL*N - c - 1 << endl;
    
  return 0;
}