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

import java.util.stream.Collectors;

public class No1345 {
	
	public static class Combination {
	    public static List<List<Integer>> make (List<Integer> candidate, int r) {
	        if (candidate.size() < r || candidate.size() <= 0 || r <= 0) {
	            List<List<Integer>> empty = new ArrayList<>();
	            empty.add(new ArrayList<>());
	            return empty;
	        }

	        List<List<Integer>> combination = new ArrayList<>();
	        for (int i = 0; i <= candidate.size() - r; i++) {
	            Integer picked = candidate.get(i);
	            List<Integer> rest = new ArrayList<>(candidate);
	            rest.subList(0, i + 1).clear();
	            combination.addAll(make(rest, r - 1).stream().map(list -> {
	                list.add(0, picked);
	                return list;
	            }).collect(Collectors.toList()));
	        }
	        return combination;
	    }
	}
	
	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 Row(Row r) {
			row = r.row;
			diag = new ArrayList<Integer>();
			cnt = r.cnt;
			col = new int[r.col.length];
			size = r.size;
		}
		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];
					}
				}
			}
		}
		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();
		Row[] RowBlt = new Row[1<<(N+2)];
		for (int i=0; i < 1 << (N+2); i++) {
			Row row = null;
			if ((i & (3 << N)) == 0) {
				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);
					}
				}
			} else {
				row = new Row(RowBlt[i & ((1 << N) - 1)]);
				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);
			RowBlt[i] = row;
		}
		List<Integer> Range = new ArrayList<Integer>();
		for (int i=0; i < N; i++) {
			Range.add(i);
		}
		int ans = Integer.MAX_VALUE;
		HashMap<Integer, List<List<Integer>>> combDict = new HashMap<Integer, List<List<Integer>>>();
		for (Row row : RowBlt) {
			if (row.size > M || M - row.size > N) {
				continue;
			} else if (row.size == M) {
				ans = Math.min(ans, row.cnt);
			} else {
				if (row.cnt >= ans) {
					continue;
				}
				List<List<Integer>> combination = null;
				if (combDict.containsKey(M-row.size)) {
					combination = combDict.get(M-row.size);
				} else {
					combination = Combination.make(Range, M-row.size);
					combDict.put(M-row.size, combination);
				}
				for (List<Integer> comb : combination) {
					int n = 0;
					for (int c : comb) {
						n += row.col[c];
						if (row.cnt + n >= ans) {
							break;
						}
					}
					ans = Math.min(ans, row.cnt + n);
				}
			}
		}
		System.out.println(ans);
	}
}