結果

問題 No.2238 Rock and Hole
ユーザー shobonvipshobonvip
提出日時 2023-03-03 22:48:15
言語 PyPy3
(7.3.15)
結果
AC  
実行時間 503 ms / 3,000 ms
コード長 4,568 bytes
コンパイル時間 219 ms
コンパイル使用メモリ 82,524 KB
実行使用メモリ 139,940 KB
最終ジャッジ日時 2024-09-17 23:55:43
合計ジャッジ時間 4,884 ms
ジャッジサーバーID
（参考情報） 		judge1 / judge3
このコードへのチャレンジ
（要ログイン）

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 58 ms
68,224 KB
testcase_01 AC 57 ms
68,608 KB
testcase_02 AC 55 ms
68,224 KB
testcase_03 AC 56 ms
68,480 KB
testcase_04 AC 56 ms
68,608 KB
testcase_05 AC 60 ms
68,480 KB
testcase_06 AC 60 ms
68,480 KB
testcase_07 AC 58 ms
68,608 KB
testcase_08 AC 58 ms
68,864 KB
testcase_09 AC 58 ms
68,224 KB
testcase_10 AC 148 ms
91,356 KB
testcase_11 AC 150 ms
102,748 KB
testcase_12 AC 150 ms
101,520 KB
testcase_13 AC 142 ms
99,468 KB
testcase_14 AC 134 ms
94,976 KB
testcase_15 AC 137 ms
85,712 KB
testcase_16 AC 308 ms
139,940 KB
testcase_17 AC 285 ms
138,876 KB
testcase_18 AC 212 ms
118,632 KB
testcase_19 AC 503 ms
114,796 KB
testcase_20 AC 299 ms
119,072 KB
testcase_21 AC 336 ms
114,368 KB
testcase_22 AC 244 ms
108,620 KB
testcase_23 AC 56 ms
69,120 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 # 

from typing import NamedTuple, Optional, List, cast

class MFGraph:
	class Edge(NamedTuple):
		src: int
		dst: int
		cap: int
		flow: int

	class _Edge:
		def __init__(self, dst: int, cap: int) -> None:
			self.dst = dst
			self.cap = cap
			self.rev: Optional[MFGraph._Edge] = None

	def __init__(self, n: int) -> None:
		self._n = n
		self._g: List[List[MFGraph._Edge]] = [[] for _ in range(n)]
		self._edges: List[MFGraph._Edge] = []

	def add_edge(self, src: int, dst: int, cap: int) -> int:
		assert 0 <= src < self._n
		assert 0 <= dst < self._n
		assert 0 <= cap
		m = len(self._edges)
		e = MFGraph._Edge(dst, cap)
		re = MFGraph._Edge(src, 0)
		e.rev = re
		re.rev = e
		self._g[src].append(e)
		self._g[dst].append(re)
		self._edges.append(e)
		return m

	def get_edge(self, i: int) -> Edge:
		assert 0 <= i < len(self._edges)
		e = self._edges[i]
		re = cast(MFGraph._Edge, e.rev)
		return MFGraph.Edge(
			re.dst,
			e.dst,
			e.cap + re.cap,
			re.cap
		)

	def edges(self) -> List[Edge]:
		return [self.get_edge(i) for i in range(len(self._edges))]

	def change_edge(self, i: int, new_cap: int, new_flow: int) -> None:
		assert 0 <= i < len(self._edges)
		assert 0 <= new_flow <= new_cap
		e = self._edges[i]
		e.cap = new_cap - new_flow
		assert e.rev is not None
		e.rev.cap = new_flow

	def flow(self, s: int, t: int, flow_limit: Optional[int] = None) -> int:
		assert 0 <= s < self._n
		assert 0 <= t < self._n
		assert s != t
		if flow_limit is None:
			flow_limit = cast(int, sum(e.cap for e in self._g[s]))

		current_edge = [0] * self._n
		level = [0] * self._n

		def fill(arr: List[int], value: int) -> None:
			for i in range(len(arr)):
				arr[i] = value

		def bfs() -> bool:
			fill(level, self._n)
			queue = []
			q_front = 0
			queue.append(s)
			level[s] = 0
			while q_front < len(queue):
				v = queue[q_front]
				q_front += 1
				next_level = level[v] + 1
				for e in self._g[v]:
					if e.cap == 0 or level[e.dst] <= next_level:
						continue
					level[e.dst] = next_level
					if e.dst == t:
						return True
					queue.append(e.dst)
			return False

		def dfs(lim: int) -> int:
			stack = []
			edge_stack: List[MFGraph._Edge] = []
			stack.append(t)
			while stack:
				v = stack[-1]
				if v == s:
					flow = min(lim, min(e.cap for e in edge_stack))
					for e in edge_stack:
						e.cap -= flow
						assert e.rev is not None
						e.rev.cap += flow
					return flow
				next_level = level[v] - 1
				while current_edge[v] < len(self._g[v]):
					e = self._g[v][current_edge[v]]
					re = cast(MFGraph._Edge, e.rev)
					if level[e.dst] != next_level or re.cap == 0:
						current_edge[v] += 1
						continue
					stack.append(e.dst)
					edge_stack.append(re)
					break
				else:
					stack.pop()
					if edge_stack:
						edge_stack.pop()
					level[v] = self._n
			return 0

		flow = 0
		while flow < flow_limit:
			if not bfs():
				break
			fill(current_edge, 0)
			while flow < flow_limit:
				f = dfs(flow_limit - flow)
				flow += f
				if f == 0:
					break
		return flow

	def min_cut(self, s: int) -> List[bool]:
		visited = [False] * self._n
		stack = [s]
		visited[s] = True
		while stack:
			v = stack.pop()
			for e in self._g[v]:
				if e.cap > 0 and not visited[e.dst]:
					visited[e.dst] = True
					stack.append(e.dst)
		return visited

h,w = map(int,input().split())
n = h*w
mf = MFGraph(2*n + 2)
s = [input() for i in range(h)]

# UPPER
upp = [[-1] * w for i in range(h)]
dwn = [[10**9] * w for i in range(h)]
rgt = [[10**9] * w for i in range(h)]
lft = [[-1] * w for i in range(h)]

for i in range(h):
	for j in range(w):
		if s[i][j] == "h":
			upp[i][j] = i
			dwn[i][j] = i
			rgt[i][j] = j
			lft[i][j] = j

for i in range(h-1):
	for j in range(w):
		upp[i+1][j] = max(upp[i][j], upp[i+1][j])

for i in range(h-2,-1,-1):
	for j in range(w):
		dwn[i][j] = min(dwn[i][j], dwn[i+1][j])

for i in range(h):
	for j in range(w-1):
		lft[i][j+1] = max(lft[i][j], lft[i][j+1])

for i in range(h):
	for j in range(w-2,-1,-1):
		rgt[i][j] = min(rgt[i][j], rgt[i][j+1])

cnt = 0
for i in range(h):
	for j in range(w):
		if s[i][j] == "r":
			if 0 <= upp[i][j] < 10**9:
				mf.add_edge(i*w+j, n+upp[i][j]*w+j, 1)
			if 0 <= dwn[i][j] < 10**9:
				mf.add_edge(i*w+j, n+dwn[i][j]*w+j, 1)
			if 0 <= lft[i][j] < 10**9:
				mf.add_edge(i*w+j, n+i*w+lft[i][j], 1)
			if 0 <= rgt[i][j] < 10**9:
				mf.add_edge(i*w+j, n+i*w+rgt[i][j], 1)
			mf.add_edge(2*n, i*w+j, 1)	
			cnt += 1
		
		if s[i][j] == "h":
			mf.add_edge(n+i*w+j, 2*n+1, 1)
	
k = mf.flow(2*n, 2*n+1)

if k == cnt:
	print("Yes")
else:
	print("No")
0