local mfl = math.floor
local n, v, sx, sy, gx, gy = io.read("*n", "*n", "*n", "*n", "*n", "*n")
local goalidx = (gy - 1) * n + gx
local map = {}
for i = 1, n * n do
  map[i] = io.read("*n")
end
local life = {}
for i = 1, n * n do
  life[i] = 0
end
local n2 = n * n
life[(sy - 1) * n + sx] = v
local alltasks = {}
alltasks[1] = {(sy - 1) * n + sx}
local curtaskidx = 1

local function walk(curidx, dstidx)
  if life[dstidx] < life[curidx] - map[dstidx] then
    if goalidx == dstidx then
      print(curtaskidx)
      return true
    end
    table.insert(alltasks[curtaskidx + 1], dstidx)
    life[dstidx] = life[curidx] - map[dstidx]
  end
  return false
end
local found = false
while 0 < #alltasks[curtaskidx] do
  alltasks[curtaskidx + 1] = {}
  for i = 1, #alltasks[curtaskidx] do
    local idx = alltasks[curtaskidx][i]
    local ret = false
    if idx % n ~= 0 then
      found = walk(idx, idx + 1)
      if found then break end
    end
    if idx % n ~= 1 then
      found = walk(idx, idx - 1)
      if found then break end
    end
    if n < idx then
      found = walk(idx, idx - n)
      if found then break end
    end
    if idx <= n * n - n then
      found = walk(idx, idx + n)
      if found then break end
    end
  end
  if found then break end
  curtaskidx = curtaskidx + 1
end
if not found then print(-1) end