import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Scanner;

public class No1345 {
	
	private static class Row {
		public List<Integer> row;
		public List<Integer> diag;
		public int cnt;
		public int[] col;
		public int size;
		public Row(int n) {
			row = new ArrayList<Integer>();
			diag = new ArrayList<Integer>();
			cnt = 0;
			col = new int[n];
			size = 0;
		}
		public void SetCol(int[][] A) {
			for (int i=0; i < col.length; i++) {
				for (int j : row) {
					if (!ContainDiag(j, i)) {
						col[i] += A[j][i];
					}
				}
			}
			Arrays.sort(col);
			for (int i=0; i < col.length-1; i++) {
				col[i+1] += col[i];
			}
		}
		public void SetDiag(int row, int col) {
			int i = (row << 16) + col;
			if (!diag.contains(i)) {
				diag.add(i);
			}
		}
		public boolean ContainDiag(int row, int col) {
			int i = (row << 16) + col;
			return diag.contains(i);
		}
	}
	
	public static void main(String[] args) {
		
		Scanner scan = new Scanner(System.in);
		int N = scan.nextInt();
		int M = scan.nextInt();
		int[] RowSum = new int[N];
		int[][] A = new int[N][N];
		for (int i=0; i < N; i++) {
			int sum = 0;
			for (int j=0; j < N; j++) {
				int a = scan.nextInt();
				sum += a;
				A[i][j] = a;
			}
			RowSum[i] = sum;
		}
		scan.close();
		int ans = Integer.MAX_VALUE;
		for (int i=0; i < 1 << (N+2); i++) {
			Row row = new Row(N);
			for (int j=0; j < N; j++) {
				if ((i & (1 << j)) != 0) {
					row.cnt += RowSum[j];
					row.size++;
				} else {
					row.row.add(j);
				}
			}
			if ((i & (3 << N)) != 0) {
				for (int j = 0; j < N; j++) {
					if (row.row.contains(j)) {
						if ((i & (1 << N)) != 0) {
							row.cnt += A[j][j];
							row.SetDiag(j, j);
						}
						if ((i & (1 << (N+1))) != 0) {
							if (!row.ContainDiag(j, N-1-j)) {
								row.cnt += A[j][N-1-j];
								row.SetDiag(j, N-1-j);
							}
						}
					}
				}
				if ((i & (1 << N)) != 0) {
					row.size++;
				}
				if ((i & (1 << (N+1))) != 0) {
					row.size++;
				}
			}
			row.SetCol(A);
			if (row.size == M) {
				ans = Math.min(ans, row.cnt);
			} else if (row.size < M && M - row.size <= N) {
				ans = Math.min(ans, row.cnt + row.col[M-row.size-1]);
			}
		}
		System.out.println(ans);
	}
}