N, V, SX, SY, GX, GY = gets.split.take(6).map(&:to_i)
MAP = N.times.map{ gets.split.take(N).map(&:to_i) }

def f(start, last)
  visited = Hash.new -1
  visited[start] = V
  q = {start=>V}

  step = 0
  while !q.empty?
    step += 1
    qq = {}
    q.each{|(x, y), hp|
      [[x+1, y], [x-1, y], [x, y+1], [x, y-1]].each{|a, b|
        next if !a.between?(0, N-1)
        next if !b.between?(0, N-1)
        _hp = hp - MAP[b][a]
        next if _hp < 1
        return step if [a, b] == last
        if visited[[a,b]] < _hp
          visited[[a,b]] = _hp
          qq[[a,b]] = _hp
        end
      }
    }
    q = qq
  end
  -1
end

p f([SX-1, SY-1], [GX-1, GY-1])