#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i=0; i<n; i++)
#define pb push_back
typedef long long ll;

int main() {
    cin.tie(0); ios::sync_with_stdio(false);
    int N, M; cin >> N >> M;
    int A[N][N];
    rep(i, N) rep(j, N) cin >> A[i][j];
    int ans = 1000000;
    
    rep(S, 1<<(N+2)) {
        int cnt = 0;
        bool flag[N][N];
        rep(i, N) rep(j, N) flag[i][j] = false;
        
        rep(i, N+2) if ((S>>i)&1) {
            cnt++;
            if (i<N) rep(j, N) flag[j][i] = true;
            else if (i==N) rep(j, N) flag[j][j] = true;
            else rep(j, N) flag[j][N-1-j] = true;
        }

        if (cnt>M) continue;
        int cand = 0;
        rep(i, N) rep(j, N) if (flag[i][j]) cand += A[i][j];
        
        vector<int> needs;
        rep(i, N) {
            int need = 0;
            rep(j, N) if (!flag[i][j]) need += A[i][j];
            needs.pb(need);
        }
        sort(needs.begin(), needs.end());
        rep(i, M-cnt) cand += needs[i];
        ans = min(ans, cand);
    }
    
    cout << ans << endl;
}