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

const int MAXN = 100;
const int MAXM = 200;

int N, M;
int C[MAXM][MAXN][MAXN];

vector<int> syugo[MAXM][MAXN + 1 << 1];

signed main() {
  ios::sync_with_stdio(false);
  cin >> N >> M;
  for (int i = 0; i < M; ++i) {
    for (int j = 0; j < N; ++j) {
      for (int k = 0; k < N; ++k) {
        cin >> C[i][j][k];
      }
    }
  }
  for (int i = 0; i < M; ++i) {
    for (int j = 0; j < N; ++j) {
      for (int k = 0; k < N; ++k) {
        syugo[i][j].emplace_back(C[i][j][k]);
        syugo[i][N + k].emplace_back(C[i][j][k]);
        if (j == k) syugo[i][N << 1].emplace_back(C[i][j][k]);
        if (N - 1 - j == k) syugo[i][N << 1 | 1].emplace_back(C[i][j][k]);
      }
    }
    for (int j = 0; j < N + 1 << 1; ++j) {
      sort(syugo[i][j].begin(), syugo[i][j].end());
    }
  }
  int ans = 2 * N;
  for (int i = 0; i < M; ++i) {
    for (int j = i + 1; j < M; ++j) {
      for (int k = 0; k < N + 1 << 1; ++k) {
        for (int l = 0; l < N + 1 << 1; ++l) {
          int pt1 = 0, pt2 = 0, cnt = 0;
          while (pt1 < N && pt2 < N) {
            if (syugo[i][k][pt1] < syugo[j][l][pt2]) ++pt1;
            else if (syugo[i][k][pt1] > syugo[j][l][pt2]) ++pt2;
            else ++pt1, ++pt2, ++cnt;
          }
          ans = min(ans, 2 * N - cnt - 1);
        }
      }
    }
  }
  cout << ans << endl;
  return 0;
}