結果

問題 No.957 植林
ユーザー lam6er
提出日時 2025-04-16 16:04:36
言語 PyPy3
(7.3.15)
結果
TLE  
実行時間 -
コード長 3,218 bytes
コンパイル時間 454 ms
コンパイル使用メモリ 81,408 KB
実行使用メモリ 158,408 KB
最終ジャッジ日時 2025-04-16 16:11:28
合計ジャッジ時間 19,500 ms
ジャッジサーバーID
(参考情報)
judge4 / judge5
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 * 3
other AC * 15 TLE * 1 -- * 29
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 #

import sys
from collections import deque

class Edge:
    def __init__(self, to, rev, capacity):
        self.to = to
        self.rev = rev
        self.capacity = capacity

class Dinic:
    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
    
    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

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()))
    
    sum_R = sum(R)
    sum_C = sum(C)
    
    # Nodes:
    # S = 0, T = 1
    # R_i: 2 ~ H+1
    # C_j: H+2 ~ H+W+1
    # X_ij: H+W+2 + i*W + j
    total_nodes = 2 + H + W + H * W
    dinic = Dinic(total_nodes)
    S = 0
    T = 1
    
    # Add edges for R_i
    for i in range(H):
        r_node = 2 + i
        cap = R[i]
        dinic.add_edge(S, r_node, cap)
    
    # Add edges for C_j
    for j in range(W):
        c_node = 2 + H + j
        cap = C[j]
        dinic.add_edge(S, c_node, cap)
    
    INF = 1 << 60
    for i in range(H):
        for j in range(W):
            x_node = 2 + H + W + i * W + j
            r_node = 2 + i
            c_node = 2 + H + j
            # Add edges from R_i and C_j to X_ij
            dinic.add_edge(r_node, x_node, INF)
            dinic.add_edge(c_node, x_node, INF)
            # Add edge from X_ij to T
            dinic.add_edge(x_node, T, G[i][j])
    
    min_cut = dinic.max_flow(S, T)
    answer = sum_R + sum_C - min_cut
    print(max(answer, 0))

if __name__ == "__main__":
    main()
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