結果

問題 No.1153 ねこちゃんゲーム
ユーザー gew1fw
提出日時 2025-06-12 19:32:50
言語 PyPy3
(7.3.15)
結果
WA  
実行時間 -
コード長 2,153 bytes
コンパイル時間 227 ms
コンパイル使用メモリ 82,692 KB
実行使用メモリ 143,184 KB
最終ジャッジ日時 2025-06-12 19:33:22
合計ジャッジ時間 26,229 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）
ファイルパターン 結果
sample AC * 2
other AC * 6 WA * 29 TLE * 1 -- * 4
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 defaultdict

def main():
    sys.setrecursionlimit(1 << 25)
    N, M = map(int, sys.stdin.readline().split())
    A = list(map(int, sys.stdin.readline().split()))
    edges = [[] for _ in range(N+1)]
    for _ in range(N-1):
        u, v = map(int, sys.stdin.readline().split())
        edges[u].append(v)
        edges[v].append(u)
    
    # Build tree and compute parent and children for each node
    # Let's root the tree at node 1
    root = 1
    parent = [0] * (N+1)
    children = [[] for _ in range(N+1)]
    stack = [(root, 0)]
    while stack:
        u, p = stack.pop()
        parent[u] = p
        for v in edges[u]:
            if v != p:
                children[u].append(v)
                stack.append((v, u))
    
    # Compute Grundy numbers using post-order traversal
    G = [0] * (N+1)
    visited = [False] * (N+1)
    stack = [(root, False)]
    while stack:
        u, processed = stack.pop()
        if processed:
            s = set()
            for v in children[u]:
                s.add(G[v])
            mex = 0
            while mex in s:
                mex += 1
            G[u] = mex
        else:
            stack.append((u, True))
            for v in reversed(children[u]):
                stack.append((v, False))
    
    # Compute XOR of Grundy numbers for all cats
    xor_sum = 0
    for a in A:
        xor_sum ^= G[a]
    
    if xor_sum == 0:
        print("-1 -1")
        return
    
    # Find the optimal move
    for i in range(M):
        a = A[i]
        current_xor = xor_sum ^ G[a]
        # For each child of a, compute new_xor and check if it is zero
        for v in edges[a]:
            if v == parent[a]:
                continue
            s = set()
            for child in children[v]:
                s.add(G[child])
            mex = 0
            while mex in s:
                mex += 1
            new_g = mex
            new_xor = current_xor ^ new_g
            if new_xor == 0:
                print(i+1, v)
                return
    
    # If no move found, which shouldn't happen
    print("-1 -1")

if __name__ == "__main__":
    main()
0