結果

問題 No.421 しろくろチョコレート
ユーザー lam6er
提出日時 2025-03-31 17:32:40
言語 PyPy3
(7.3.15)
結果
AC  
実行時間 133 ms / 2,000 ms
コード長 3,028 bytes
コンパイル時間 239 ms
コンパイル使用メモリ 82,488 KB
実行使用メモリ 78,760 KB
最終ジャッジ日時 2025-03-31 17:33:40
合計ジャッジ時間 6,451 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
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ファイルパターン 結果
other AC * 65
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ソースコード

diff #

import sys
from collections import deque, defaultdict

def main():
    input = sys.stdin.read().split()
    idx = 0
    N = int(input[idx]); idx += 1
    M = int(input[idx]); idx += 1
    grid = []
    for _ in range(N):
        grid.append(input[idx])
        idx += 1
    
    total_white = 0
    total_black = 0
    white_nodes = []
    black_nodes = []
    for i in range(N):
        for j in range(M):
            c = grid[i][j]
            if c == 'w':
                total_white += 1
                white_nodes.append((i, j))
            elif c == 'b':
                total_black += 1
                black_nodes.append((i, j))
    
    method3 = 0
    if white_nodes and black_nodes:
        white_id = {(i, j): idx for idx, (i, j) in enumerate(white_nodes)}
        black_id = {(i, j): idx for idx, (i, j) in enumerate(black_nodes)}
        graph = defaultdict(list)
        for idx_w, (i, j) in enumerate(white_nodes):
            for dx, dy in [(-1, 0), (1, 0), (0, -1), (0, 1)]:
                ni, nj = i + dx, j + dy
                if 0 <= ni < N and 0 <= nj < M:
                    if grid[ni][nj] == 'b':
                        if (ni, nj) in black_id:
                            graph[idx_w].append(black_id[(ni, nj)])
        
        # Hopcroft-Karp algorithm implementation
        pair_U = [None] * len(white_nodes)
        pair_V = [None] * len(black_nodes)
        dist = [0] * len(white_nodes)
        
        def bfs():
            queue = deque()
            for u in range(len(white_nodes)):
                if pair_U[u] is None:
                    dist[u] = 0
                    queue.append(u)
                else:
                    dist[u] = float('inf')
            dist_null = float('inf')
            while queue:
                u = queue.popleft()
                if dist[u] < dist_null:
                    for v in graph[u]:
                        if pair_V[v] is None:
                            dist_null = dist[u] + 1
                        elif dist[pair_V[v]] == float('inf'):
                            dist[pair_V[v]] = dist[u] + 1
                            queue.append(pair_V[v])
            return dist_null != float('inf')
        
        def dfs(u):
            for v in graph[u]:
                if pair_V[v] is None or (dist[pair_V[v]] == dist[u] + 1 and dfs(pair_V[v])):
                    pair_U[u] = v
                    pair_V[v] = u
                    return True
            dist[u] = float('inf')
            return False
        
        method3 = 0
        while bfs():
            for u in range(len(white_nodes)):
                if pair_U[u] is None:
                    if dfs(u):
                        method3 += 1
    
    remaining_white = total_white - method3
    remaining_black = total_black - method3
    method2 = min(remaining_white, remaining_black)
    method1 = (remaining_white - method2) + (remaining_black - method2)
    total = 100 * method3 + 10 * method2 + method1
    print(total)

if __name__ == '__main__':
    main()
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