#include <bits/stdc++.h>
using namespace std;
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) begin(v),end(v)
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }
using ll = long long;
using pii = pair<int, int>;
constexpr ll INF = 1ll<<30;
constexpr ll longINF = 1ll<<60;
constexpr ll MOD = 1000000007;
constexpr bool debug = false;
//---------------------------------//

int main() {
	int N, M;
	cin >> N >> M;
	vector A(N, vector<int>(N));
	REP(i, N) REP(j, N) scanf("%d", &A[i][j]);
	vector<int> sum(N); // 行
	REP(i, N) REP(j, N) sum[i] += A[i][j];
	
	int ans = INF;
	REP(i, 1 << N) { // 列
		REP(j, 4) { // 1:右下(+1,+1), 2:左下(+1,-1)
			int res = M;
			REP(k, N) if (i >> k & 1) --res;
			if (j & 1) --res;
			if (j & 2) --res;
			if (res < 0) continue;
			vector<int> dp(res + 1, INF), ndp;
			dp[0] = 0;
			REP(k, N) { // 行
				int cost = 0;
				REP(l, N) if ((i >> l & 1) || (j & 1) && k == l || (j & 2) && N - 1 - k == l) cost += A[k][l];
				ndp.assign(res + 1, INF);
				REP(l, res + 1) {
					if (dp[l] == INF) continue;
					chmin(ndp[l], dp[l] + cost);
					if (l < res) chmin(ndp[l + 1], dp[l] + sum[k]);
				}
				swap(ndp, dp);
			}
			chmin(ans, dp[res]);
		}
	}
	cout << ans << endl;
}