#include <bits/stdc++.h>
#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(v) v.begin(), v.end()
using namespace std;
using P = pair<int, int>;
typedef long long ll;
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
const int dx[4] = {1, 0, -1, 0};
const int dy[4] = {0, 1, 0, -1};

int main() {
  int n, m;
  cin >> n >> m;
  ll ans = (1LL << 60);
  vector<vector<int>> A(n, vector<int>(n));
  rep(i, n) rep(j, n) cin >> A[i][j];
  for (int bit = 1; bit < (1 << (2 * n + 2)); bit++){
    int d = __builtin_popcount(bit);
    vector<vector<int>> cnt(n, vector<int>(n, 0));
    if(d != m)continue;
    ll res = 0;
    rep(i, 2 *n +2){
      if(bit & (1 << i)){
        if(i < n){
          rep(j, n){
            res += A[i][j];
            cnt[i][j]++;
          }
        }else if(i >= n && i < 2 * n){
          rep(j, n){
            res += A[j][i - n];
            cnt[j][i- n]++;
          }
        }else{
          if(i == 2 * n){
            rep(j, n){
              res += A[j][j];
              cnt[j][j]++;
            }
          }else{
            rep(j, n){
              res += A[j][n -1- j];
              cnt[j][n -1-  j]++;
            }
          }
        }
      }
    }
    rep(i, n){
      rep(j, n){
        if(cnt[i][j] > 1)res -= A[i][j] * (cnt[i][j] - 1);
      }
    }
    chmin(ans, res);
  }
  cout << ans << endl;
}