結果

問題 No.59 鉄道の旅
コンテスト
ユーザー 👑 obakyan
提出日時 2020-04-25 11:18:10
言語 Lua
(LuaJit 2.1.1734355927)
結果
AC  
実行時間 171 ms / 5,000 ms
コード長 2,690 bytes
コンパイル時間 98 ms
コンパイル使用メモリ 6,820 KB
実行使用メモリ 15,072 KB
最終ジャッジ日時 2024-11-06 20:43:24
合計ジャッジ時間 1,557 ms
ジャッジサーバーID
（参考情報） 		judge4 / judge2
このコードへのチャレンジ
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ファイルパターン 結果
sample AC * 4
other AC * 12
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 mab = math.abs
local mfl, mce = math.floor, math.ceil
local mmi, mma = math.min, math.max
local bls, brs = bit.lshift, bit.rshift
local SegTree = {}
SegTree.updateAll = function(self)
  for i = self.stagenum - 1, 1, -1 do
    local cnt = bls(1, i - 1)
    for j = 1, cnt do
      self.stage[i][j] = self.func(self.stage[i + 1][j * 2 - 1], self.stage[i + 1][j * 2])
    end
  end
end
SegTree.create = function(self, n, func, emptyvalue)
  self.func, self.emptyvalue = func, emptyvalue
  local stagenum, mul = 1, 1
  self.stage = {{}}
  while mul < n do
    mul, stagenum = mul * 2, stagenum + 1
    self.stage[stagenum] = {}
  end
  self.stagenum = stagenum
  self.left_stage = {}
  for i = 1, n do
    local sp, sz = 1, bls(1, stagenum - 1)
    while(i - 1) % sz ~= 0 do
      sp, sz = sp + 1, brs(sz, 1)
    end
    self.left_stage[i] = sp
  end
  self.sz_stage = {}
  local tmp, sp = 1, stagenum
  for i = 1, n do
    if tmp * 2 == i then tmp, sp = tmp * 2, sp - 1 end
    self.sz_stage[i] = sp
  end
  for i = 1, mul do self.stage[stagenum][i] = emptyvalue end
  self:updateAll()
end
SegTree.getRange = function(self, left, right)
  if left == right then return self.stage[self.stagenum][left] end
  local stagenum = self.stagenum
  local ret = self.emptyvalue
  while left <= right do
    local stage = mma(self.left_stage[left], self.sz_stage[right - left + 1])
    local sz = bls(1, stagenum - stage)
    ret = self.func(ret, self.stage[stage][1 + brs(left - 1, stagenum - stage)])
    left = left + sz
  end
  return ret
end
SegTree.addValue = function(self, idx, value)
  self.stage[self.stagenum][idx] = mma(0, self.stage[self.stagenum][idx] + value)
  for i = self.stagenum - 1, 1, -1 do
    local dst = brs(idx + 1, 1)
    local rem = dst * 4 - 1 - idx
    self.stage[i][dst] = self.func(self.stage[i + 1][idx], self.stage[i + 1][rem])
    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, k = io.read("*n", "*n")
local w = {}
for i = 1, n do
  w[i] = io.read("*n")
end
local wuniq, wuniq_m = {}, {}
for i = 1, n do
  local v = mab(w[i])
  if not wuniq_m[v] then
    table.insert(wuniq, v)
    wuniq_m[v] = true
  end
end
table.sort(wuniq)
local w_inv = {}
for i = 1, #wuniq do
  w_inv[wuniq[i]] = i
end
local st = SegTree.new(#wuniq, function(a, b) return a + b end, 0)
for i = 1, n do
  local v = w[i]
  if v < 0 then
    v = -v
    local pos = w_inv[v]
    st:addValue(pos, -1)
  else
    local pos = w_inv[v]
    local cnt = st:getRange(pos, #wuniq)
    if cnt < k then
      st:addValue(pos, 1)
    end
  end
end
print(st.stage[1][1])
0