io.input("test")
--io.input("input")

function p2s( x, y )
  return string.format("%d,%d", x, y)
end

function s2p( s )
  local x, y = string.match(s,"(-?%d+),(-?%d+)")
  x = tonumber(x)
  y = tonumber(y)
  return x, y
end

function neighbors(x, y)
  local n = {}
  n.NW = p2s( x-1, y-1)
  n.N = p2s( x, y-1)
  n.NE = p2s( x+1, y-1)
  n.E = p2s( x+1, y )
  n.SE = p2s(x+1, y+1)
  n.S = p2s(x, y+1)
  n.SW = p2s(x-1, y+1)
  n.W = p2s(x-1, y)
  return n
end

local max = {y=0, x=0}
local min = {y=10000, x=10000}
function updateMaxMin( j, i )
  if j>max.x then max.x = j
  elseif j<min.x then min.x = j end
  if i>max.y then max.y = i 
  elseif i<min.y then min.y = i end
end

local nelves = 0
local elves = {}

-- parse map
local i = 1
for line in io.lines() do
  local j = 1
  for c in string.gmatch(line, "%g") do
    if c=="#" then
      elves[ p2s(j,i) ] = true
      updateMaxMin(j, i)
      nelves = nelves + 1
    end
    j = j + 1
  end
  i = i + 1
end


local dirs = {"N", "S", "W", "E"}
local offdirs = 0
local round = 1
local result1
repeat
  -- first half
  local attempts = {} 
  for s, e in pairs(elves) do
    local x, y = s2p(s)

    local alone = true
    local n = neighbors(x,y)
    for k, ns in pairs(n) do
      if elves[ns] then alone = false break end
    end
    if alone then goto continue end

    for i=0,3 do
      local idirs = (i+offdirs)%4 + 1
      local dir = dirs[idirs]
      if dir=="N" and not (elves[n.NW] or elves[n.N] or elves[n.NE]) then
        --print("propose north")
        if attempts[n.N] == nil then
          attempts[n.N] = s
        elseif attempts[n.N] then -- attempt
          attempts[n.N] = false
        end
        break
      elseif dir=="S" and not (elves[n.SW] or elves[n.S] or elves[n.SE]) then
       --print("propose south")
        if attempts[n.S] == nil then
          attempts[n.S] = s
        elseif attempts[n.S] then -- attempt
          attempts[n.S] = false
        end
        break
      elseif dir=="W" and not (elves[n.SW] or elves[n.W] or elves[n.NW]) then
        --print("propose west")
        if attempts[n.W] == nil then
          attempts[n.W] = s
        elseif attempts[n.W] then -- attempt
          attempts[n.W] = false
        end
        break
      elseif dir=="E" and not (elves[n.SE] or elves[n.E] or elves[n.NE]) then
       -- print("propose east")
        if attempts[n.E] == nil then
          attempts[n.E] = s
        elseif attempts[n.E] then -- attempt
          attempts[n.E] = false
        end
        break
      end
    end

    ::continue::
  end

  --second half
  local count = 0
  for k, s in pairs(attempts) do
    if s then 
      elves[s] = nil
      elves[k] = true
      local nx, ny = s2p(k)
      updateMaxMin(nx, ny)
      count = count + 1
    end
  end

  --[[
  print("moved:",count)
  print(min.x, min.y, max.x, max.y)
  --]]

  offdirs = (offdirs==3) and 0 or (offdirs+1)

  if round%100==0 then
    print("round", round)
  end

  if round == 10 then
    result1 = (max.y-min.y+1)*(max.x-min.x+1)-nelves
  end

  if count > 0 then
    round = round + 1
  end
until count == 0

print("part 1", result1)
print("part 2", round)

-- print map:
for y=min.y,max.y do
  local m = ""
  for x=min.x,max.x do
    local s = p2s(x,y)
    m = m .. (elves[s] and "#" or ".")
  end
--  print(m)
end