// Template
#include "bits/stdc++.h"
#define rep_override(x, y, z, name, ...) name
#define rep2(i, n) for (int i = 0; i < (int)(n); ++i)
#define rep3(i, l, r) for (int i = (int)(l); i < (int)(r); ++i)
#define rep(...) rep_override(__VA_ARGS__, rep3, rep2)(__VA_ARGS__)
#define all(x) (x).begin(), (x).end()
using namespace std;
using ll = long long;
constexpr int inf = 1001001001;
constexpr ll infll = 3003003003003003003LL;
template <typename T>
inline bool chmin(T &x, const T &y) {
    if (x > y) {
        x = y;
        return true;
    }
    return false;
}
template <typename T> 
inline bool chmax(T &x, const T &y) {
    if (x < y) {
        x = y;
        return true;
    }
    return false;
}
template <typename T>
istream &operator>>(istream &is, vector<T> &vec) {
    for (T &element : vec) is >> element;
    return is;
}
template <typename T>
ostream &operator<<(ostream &os, const vector<T> &vec) {
    for (int i = 0, vec_len = (int)vec.size(); i < vec_len; ++i) {
        os << vec[i] << (i + 1 == vec_len ? "" : " ");
    }
    return os;
}
struct IOSET {
    IOSET() {
        cin.tie(nullptr);
        ios::sync_with_stdio(false);
        cout << fixed << setprecision(10);
    }
} ioset;

// Main
int main() {
    int n, m;
    cin >> n >> m;
    vector<vector<ll>> a(n, vector<ll>(n));
    cin >> a;
    
    ll ans = infll;
    
    rep(bit, 1 << (n + 2)) {
        vector<vector<int>> vec(n, vector<int>(n, 0));
        int cnt = 0;
        ll sum = 0;
        rep(j, n) {
            if (bit & (1 << j)) {
                rep(k, n) {
                    if (!exchange(vec[j][k], 1)) sum += a[j][k];
                }
                ++cnt;
            }
        }
        if (bit & (1 << (n))) {
            rep(i, n) {
                if (!exchange(vec[i][i], 1)) sum += a[i][i];
            }
            ++cnt;
        }
        if (bit & (1 << (n + 1))) {
            rep(i, n) {
                if (!exchange(vec[i][n - 1 - i], 1)) sum += a[i][n - 1 - i];
            }
            ++cnt;
        }
        vector<ll> aaa;
        rep(i, n) {
            bool f = true;
            ll iii = 0;
            rep(j, n) if (!vec[j][i]) {
                f = false;
                iii += a[j][i];
            }
            if (f) ++cnt;
            else aaa.push_back(iii);
        }
        if (cnt >= m) {
            chmin(ans, sum);
            continue;
        }
        if (m - cnt > aaa.size()) continue;
        sort(all(aaa));
        rep(i, m - cnt) {
            sum += aaa[i];
        }
        chmin(ans, sum);
    }
    
    cout << ans << "\n";
}