import sys
from itertools import combinations

def main():
    input = sys.stdin.read().split()
    idx = 0
    N = int(input[idx]); idx +=1
    M = int(input[idx]); idx +=1

    A = []
    for _ in range(N):
        row = list(map(int, input[idx:idx+N]))
        idx +=N
        A.append(row)

    # Enumerate all lines
    lines = []

    # Rows
    for i in range(N):
        cells = []
        total = 0
        for j in range(N):
            val = A[i][j]
            cells.append((i, j))
            total += val
        lines.append( (total, cells) )

    # Columns
    for j in range(N):
        cells = []
        total = 0
        for i in range(N):
            val = A[i][j]
            cells.append((i, j))
            total += val
        lines.append( (total, cells) )

    # Diagonals
    # Top-left to bottom-right
    cells = []
    total = 0
    for i in range(N):
        j = i
        val = A[i][j]
        cells.append((i, j))
        total += val
    lines.append( (total, cells) )

    # Top-right to bottom-left
    cells = []
    total = 0
    for i in range(N):
        j = N - 1 - i
        val = A[i][j]
        cells.append((i, j))
        total += val
    lines.append( (total, cells) )

    min_total = float('inf')

    # Generate all possible combinations of lines with size from M to len(lines)
    for k in range(M, len(lines)+1):
        for selected in combinations(range(len(lines)), k):
            covered = set()
            for idx_line in selected:
                for (i,j) in lines[idx_line][1]:
                    covered.add( (i,j) )
            current_sum = 0
            for (i,j) in covered:
                current_sum += A[i][j]
            if current_sum < min_total:
                min_total = current_sum

    print(min_total)

if __name__ == "__main__":
    main()