#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for(int i = 0; i < n; i++)
#define rep2(i, x, n) for(int i = x; i <= n; i++)
#define rep3(i, x, n) for(int i = x; i >= n; i--)
#define each(e, v) for(auto &e: v)
#define pb push_back
#define eb emplace_back
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define sz(x) (int)x.size()
using ll = long long;
using pii = pair<int, int>;
using pil = pair<int, ll>;
using pli = pair<ll, int>;
using pll = pair<ll, ll>;
const int MOD = 1000000007;
//const int MOD = 998244353;
const int inf = (1<<30)-1;
const ll INF = (1LL<<60)-1;
template<typename T> bool chmax(T &x, const T &y) {return (x < y)? (x = y, true) : false;};
template<typename T> bool chmin(T &x, const T &y) {return (x > y)? (x = y, true) : false;};

struct io_setup{
    io_setup(){
        ios_base::sync_with_stdio(false);
        cin.tie(NULL);
        cout << fixed << setprecision(15);
    }
} io_setup;

int main(){
    int N, M;
    cin >> N >> M;

    vector<vector<int>> c(N, vector<int>(N));
    rep(i, N){
        rep(j, N) cin >> c[i][j];
    }

    int ans = inf;
    rep(i, 2) rep(j, 2) rep(k, 1<<N){
        vector<vector<bool>> used(N, vector<bool>(N, false));
        rep(l, N){
            if(i) used[l][l] = true;
            if(j) used[N-1-l][l] = true;
        }
        rep(x, N){
            if(k&(1<<x)){
                rep(y, N) used[x][y] = true;
            }
        }
        int tmp = 0;
        rep(x, N){
            rep(y, N){
                if(used[x][y]) tmp += c[x][y];
            }
        }
        vector<int> ws(N);
        rep(y, N){
            int s = 0;
            rep(x, N){
                if(!used[x][y]) s += c[x][y];
            }
            ws[y] = s;
        }
        sort(all(ws));
        int rem = M-i-j-__builtin_popcount(k);
        if(rem > N) continue;
        rep(l, rem) tmp += ws[l];
        chmin(ans, tmp);
    }

    cout << ans << '\n';
}