#include <bits/stdc++.h>
using namespace std;
const int INF = 10000000;
int main(){
  int N, M;
  cin >> N >> M;
  vector<vector<int>> A(N, vector<int>(N));
  for (int i = 0; i < N; i++){
    for (int j = 0; j < N; j++){
      cin >> A[i][j];
    }
  }
  int ans = INF;
  for (int i = 0; i < 2; i++){
    for (int j = 0; j < 2; j++){
      int sum = 0;
      vector<vector<int>> B = A;
      for (int k = 0; k < N; k++){
        for (int l = 0; l < N; l++){
          if (i == 1 && k == l || j == 1 && k + l == N - 1){
            sum += A[k][l];
            B[k][l] = 0;
          }
        }
      }
      for (int k = 0; k < (1 << N); k++){
        int cnt = i + j + __builtin_popcount(k);
        if (M - cnt >= 0 && M - cnt <= N){
          vector<int> c(N, 0);
          int add = 0;
          for (int l = 0; l < N; l++){
            for (int m = 0; m < N; m++){
              if (!(k >> l & 1)){
                c[m] += B[l][m];
              } else {
                add += B[l][m];
              }
            }
          }
          sort(c.begin(), c.end());
          for (int l = 0; l < M - cnt; l++){
            add += c[l];
          }
          ans = min(ans, sum + add);
        }
      }
    }
  }
  cout << ans << endl;
}