結果

問題 No.977 アリス仕掛けの摩天楼
ユーザー hiragnhiragn
提出日時 2022-11-29 14:14:04
言語 Python3
(3.12.2 + numpy 1.26.4 + scipy 1.12.0)
結果
AC  
実行時間 768 ms / 2,000 ms
コード長 2,264 bytes
コンパイル時間 173 ms
コンパイル使用メモリ 13,056 KB
実行使用メモリ 40,832 KB
最終ジャッジ日時 2024-04-16 09:16:54
合計ジャッジ時間 6,515 ms
ジャッジサーバーID
(参考情報)
judge3 / judge5
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 32 ms
10,880 KB
testcase_01 AC 31 ms
10,880 KB
testcase_02 AC 32 ms
10,880 KB
testcase_03 AC 32 ms
10,880 KB
testcase_04 AC 31 ms
10,880 KB
testcase_05 AC 32 ms
10,880 KB
testcase_06 AC 32 ms
10,880 KB
testcase_07 AC 33 ms
10,880 KB
testcase_08 AC 33 ms
10,880 KB
testcase_09 AC 32 ms
10,880 KB
testcase_10 AC 32 ms
10,880 KB
testcase_11 AC 33 ms
11,008 KB
testcase_12 AC 32 ms
11,008 KB
testcase_13 AC 94 ms
13,824 KB
testcase_14 AC 94 ms
13,952 KB
testcase_15 AC 91 ms
13,952 KB
testcase_16 AC 94 ms
13,824 KB
testcase_17 AC 95 ms
13,952 KB
testcase_18 AC 224 ms
19,712 KB
testcase_19 AC 235 ms
19,968 KB
testcase_20 AC 380 ms
25,216 KB
testcase_21 AC 589 ms
33,408 KB
testcase_22 AC 749 ms
39,680 KB
testcase_23 AC 758 ms
40,704 KB
testcase_24 AC 733 ms
40,832 KB
testcase_25 AC 768 ms
40,704 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 #

class UnionFind:
    n = 1
    parent_or_size = [-1 for i in range(n)]

    def __init__(self, N):
        self.n = N
        self.parent_or_size = [-1 for _ in range(N)]

    def merge(self, a, b):
        assert 0 <= a < self.n, "0<=a<n,a={0},n={1}".format(a, self.n)
        assert 0 <= b < self.n, "0<=b<n,b={0},n={1}".format(b, self.n)
        x = self.leader(a)
        y = self.leader(b)
        if x == y:
            return x
        if -self.parent_or_size[x] < -self.parent_or_size[y]:
            x, y = y, x
        self.parent_or_size[x] += self.parent_or_size[y]
        self.parent_or_size[y] = x
        return x

    def same(self, a, b):
        assert 0 <= a < self.n, "0<=a<n,a={0},n={1}".format(a, self.n)
        assert 0 <= b < self.n, "0<=b<n,b={0},n={1}".format(b, self.n)
        return self.leader(a) == self.leader(b)

    def leader(self, a):
        assert 0 <= a < self.n, "0<=a<n,a={0},n={1}".format(a, self.n)
        if self.parent_or_size[a] < 0:
            return a
        self.parent_or_size[a] = self.leader(self.parent_or_size[a])
        return self.parent_or_size[a]

    def size(self, a):
        assert 0 <= a < self.n, "0<=a<n,a={0},n={1}".format(a, self.n)
        return -self.parent_or_size[self.leader(a)]

    def groups(self):
        leader_buf = [0 for _ in range(self.n)]
        group_size = [0 for _ in range(self.n)]
        for i in range(self.n):
            leader_buf[i] = self.leader(i)
            group_size[leader_buf[i]] += 1
        result = [[] for _ in range(self.n)]
        for i in range(self.n):
            result[leader_buf[i]].append(i)
        result2 = []
        for i in range(self.n):
            if len(result[i]) > 0:
                result2.append(result[i])
        return result2


def main():
    n = int(input())

    uf = UnionFind(n)
    adj = [[] for _ in range(n)]
    for _ in range(n - 1):
        a, b = map(int, input().split())
        uf.merge(a, b)
        adj[a].append(b)
        adj[b].append(a)

    k = len(uf.groups())
    if k == 1:
        exit(print("Bob"))
    if k > 2:
        exit(print("Alice"))
    if k == 2:
        if 1 in map(len, adj):
            print("Alice")
        else:
            print("Bob")


if __name__ == "__main__":
    main()
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