n, m = read_line.split.map(&.to_i)
a = (1..n).map { read_line.split.map(&.to_i) }
puts [false, true].repeated_permutations(n + 2).min_of { |flag|
  cnt = flag.count(true)
  b = [0] * n
  sum = 0
  (0...n).each { |i|
    (0...n).each { |j|
      if flag[i] || (flag[-2] && i == j) || (flag[-1] && i == (n - 1 - j))
        sum += a[i][j]
      else
        b[j] += a[i][j]
      end
    }
  }
  cnt + n < m ? 10**9 : sum + b.sort[0, {m - cnt, 0}.max].sum
}