結果
| 問題 |
No.957 植林
|
| コンテスト | |
| ユーザー |
lam6er
|
| 提出日時 | 2025-03-26 15:54:35 |
| 言語 | PyPy3 (7.3.15) |
| 結果 |
TLE
|
| 実行時間 | - |
| コード長 | 3,838 bytes |
| コンパイル時間 | 353 ms |
| コンパイル使用メモリ | 82,364 KB |
| 実行使用メモリ | 187,960 KB |
| 最終ジャッジ日時 | 2025-03-26 15:55:42 |
| 合計ジャッジ時間 | 17,764 ms |
|
ジャッジサーバーID (参考情報) |
judge3 / judge1 |
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| ファイルパターン | 結果 |
|---|---|
| sample | AC * 3 |
| other | AC * 15 TLE * 1 -- * 29 |
ソースコード
import sys
from collections import deque
class Edge:
def __init__(self, to, rev, capacity):
self.to = to
self.rev = rev
self.capacity = capacity
class MaxFlow:
def __init__(self, n):
self.size = n
self.graph = [[] for _ in range(n)]
def add_edge(self, fr, to, cap):
forward = Edge(to, len(self.graph[to]), cap)
backward = Edge(fr, len(self.graph[fr]), 0)
self.graph[fr].append(forward)
self.graph[to].append(backward)
def bfs_level(self, s, t, level):
q = deque()
level[:] = [-1] * self.size
level[s] = 0
q.append(s)
while q:
v = q.popleft()
for edge in self.graph[v]:
if edge.capacity > 0 and level[edge.to] == -1:
level[edge.to] = level[v] + 1
q.append(edge.to)
if edge.to == t:
return
return
def dfs_flow(self, v, t, upTo, iter_, level):
if v == t:
return upTo
for i in range(iter_[v], len(self.graph[v])):
edge = self.graph[v][i]
if edge.capacity > 0 and level[v] < level[edge.to]:
d = self.dfs_flow(edge.to, t, min(upTo, edge.capacity), iter_, level)
if d > 0:
edge.capacity -= d
self.graph[edge.to][edge.rev].capacity += d
return d
iter_[v] += 1
return 0
def max_flow(self, s, t):
flow = 0
level = [-1] * self.size
while True:
self.bfs_level(s, t, level)
if level[t] == -1:
return flow
iter_ = [0] * self.size
while True:
f = self.dfs_flow(s, t, float('inf'), iter_, level)
if f == 0:
break
flow += f
level = [-1] * self.size
return flow
def main():
H, W = map(int, sys.stdin.readline().split())
G = []
for _ in range(H):
G.append(list(map(int, sys.stdin.readline().split())))
R = list(map(int, sys.stdin.readline().split()))
C = list(map(int, sys.stdin.readline().split()))
# Compute A and B
A = []
for i in range(H):
total = sum(G[i])
A.append(R[i] - total)
B = []
for j in range(W):
total = sum(G[i][j] for i in range(H))
B.append(C[j] - total)
# Compute the sum of positive terms for maximum possible
total_positive = 0
# Create nodes: rows (0..H-1), cols (H..H+W-1), edges (H+W..H+W+H*W-1)
edge_node_start = H + W
total_nodes = edge_node_start + H * W
S = total_nodes
T = S + 1
mf = MaxFlow(T + 1)
INF = 1 << 60
# Add row nodes
for i in range(H):
a = A[i]
if a > 0:
mf.add_edge(S, i, a)
total_positive += a
else:
mf.add_edge(i, T, -a)
# Add column nodes
for j in range(W):
b = B[j]
if b > 0:
mf.add_edge(S, H + j, b)
total_positive += b
else:
mf.add_edge(H + j, T, -b)
# Add edge nodes for each i,j
for i in range(H):
for j in range(W):
g = G[i][j]
edge_node = edge_node_start + i * W + j
if g > 0:
mf.add_edge(S, edge_node, g)
total_positive += g
else:
mf.add_edge(edge_node, T, -g)
# Add edges from edge_node to row i and column j
mf.add_edge(edge_node, i, INF)
mf.add_edge(edge_node, H + j, INF)
max_flow_val = mf.max_flow(S, T)
result = total_positive - max_flow_val
print(result)
if __name__ == "__main__":
main()
lam6er