結果

問題 No.848 なかよし旅行
ユーザー 👑 obakyanobakyan
提出日時 2021-07-29 21:36:00
言語 Lua
(LuaJit 2.1.1696795921)
結果
AC  
実行時間 234 ms / 2,000 ms
コード長 2,700 bytes
コンパイル時間 147 ms
コンパイル使用メモリ 5,236 KB
実行使用メモリ 9,284 KB
最終ジャッジ日時 2023-10-12 19:37:55
合計ジャッジ時間 3,120 ms
ジャッジサーバーID
（参考情報） 		judge15 / judge11
このコードへのチャレンジ（β）

テストケース

テストケース表示
入力 結果 実行時間
実行使用メモリ
testcase_00 AC 234 ms
6,864 KB
testcase_01 AC 4 ms
4,352 KB
testcase_02 AC 1 ms
4,348 KB
testcase_03 AC 2 ms
4,348 KB
testcase_04 AC 2 ms
4,352 KB
testcase_05 AC 3 ms
4,348 KB
testcase_06 AC 4 ms
4,352 KB
testcase_07 AC 3 ms
4,348 KB
testcase_08 AC 6 ms
4,352 KB
testcase_09 AC 7 ms
4,352 KB
testcase_10 AC 7 ms
4,352 KB
testcase_11 AC 49 ms
4,976 KB
testcase_12 AC 62 ms
5,540 KB
testcase_13 AC 81 ms
6,944 KB
testcase_14 AC 31 ms
4,352 KB
testcase_15 AC 76 ms
6,692 KB
testcase_16 AC 126 ms
9,284 KB
testcase_17 AC 88 ms
7,968 KB
testcase_18 AC 46 ms
4,720 KB
testcase_19 AC 41 ms
4,348 KB
testcase_20 AC 22 ms
4,352 KB
testcase_21 AC 101 ms
7,916 KB
testcase_22 AC 78 ms
4,436 KB
testcase_23 AC 61 ms
4,348 KB
testcase_24 AC 2 ms
4,348 KB
testcase_25 AC 149 ms
9,200 KB
testcase_26 AC 1 ms
4,352 KB
testcase_27 AC 1 ms
4,348 KB
testcase_28 AC 1 ms
4,352 KB
testcase_29 AC 1 ms
4,348 KB
権限があれば一括ダウンロードができます

ソースコード

diff # 

local mfl, mce = math.floor, math.ceil
local mmi, mma = math.min, math.max
local pow2 = {1}
for i = 2, 28 do pow2[i] = pow2[i - 1] * 2 end
local SegTree = {}
SegTree.updateAll = function(self)
  for i = self.stagenum - 1, 1, -1 do
    local cnt = pow2[i]
    for j = 0, cnt - 1 do
      self.stage[cnt + j] = self.func(self.stage[(cnt + j) * 2], self.stage[(cnt + j) * 2 + 1])
    end
  end
end
SegTree.create = function(self, n, func, emptyvalue)
  self.func, self.emptyvalue = func, emptyvalue
  local stagenum, mul = 1, 1
  self.stage = {} -- use 1D Tree (stage[], not stage[][])
  while mul < n do
    mul, stagenum = mul * 2, stagenum + 1
  end
  self.stagenum = stagenum
  for i = 1, mul * 2 - 1 do self.stage[i] = emptyvalue end
  for i = 1, n do self.stage[mul + i - 1] = i end
  self:updateAll()
end
SegTree.update = function(self, idx, force)
  idx = idx + pow2[self.stagenum] - 1
  for i = self.stagenum - 1, 1, -1 do
    local dst = mfl(idx / 2)
    local rem = dst * 4 + 1 - idx
    self.stage[dst] = self.func(self.stage[idx], self.stage[rem])
    if not force and self.stage[dst] ~= self.stage[idx] then break end
    idx = dst
  end
end
SegTree.new = function(n, func, emptyvalue)
  local obj = {}
  setmetatable(obj, {__index = SegTree})
  obj:create(n, func, emptyvalue)
  return obj
end

local n, m = io.read("*n", "*n")
local p, q, t = io.read("*n", "*n", "*n")
local edge = {}
for i = 1, n do
  edge[i] = {}
end
for i = 1, m do
  local a, b, c = io.read("*n", "*n", "*n")
  edge[a][b], edge[b][a] = c, c
end

local inf = 1000000007 * 2000

local function getlen(spos)
  local len = {}
  local asked = {}
  for i = 1, n do
    len[i] = inf
    asked[i] = false
  end
  len[spos] = 0
  asked[n + 1] = true

  local function mergefunc(x, y)
    if asked[x] then return y
    elseif asked[y] then return x
    else
      return len[x] < len[y] and x or y
    end
  end

  local st = SegTree.new(n, mergefunc, n + 1)

  for i = 1, n do
    local src = st.stage[1]
    if asked[src] then break end
    if inf <= len[src] then break end
    asked[src] = true
    st:update(src, true)
    for dst, cost in pairs(edge[src]) do
      if len[src] + cost < len[dst] then
        len[dst] = len[src] + cost
        st:update(dst)
      end
    end
  end
  return len
end

local len_1 = getlen(1)
local len_p = getlen(p)
local len_q = getlen(q)

if len_1[p] + len_1[q] + len_p[q] <= t then
  print(t) os.exit()
end

local ret = -1
for i = 1, n do
  for j = 1, n do
    local lenpq = mma(len_p[i] + len_p[j], len_q[i] + len_q[j])
    local lentot = len_1[i] + len_1[j] + lenpq
    if lentot <= t then
      if ret < t - lenpq then
        ret = t - lenpq
      end
    end
  end
end
print(ret)
0