結果
問題 | No.2504 NOT Path Painting |
ユーザー | suisen |
提出日時 | 2023-07-22 17:41:32 |
言語 | PyPy3 (7.3.15) |
結果 |
AC
|
実行時間 | 498 ms / 2,000 ms |
コード長 | 2,183 bytes |
コンパイル時間 | 309 ms |
コンパイル使用メモリ | 87,284 KB |
実行使用メモリ | 119,296 KB |
最終ジャッジ日時 | 2023-10-13 18:15:01 |
合計ジャッジ時間 | 10,044 ms |
ジャッジサーバーID (参考情報) |
judge13 / judge12 |
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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 | 168 ms
79,976 KB |
testcase_01 | AC | 391 ms
84,896 KB |
testcase_02 | AC | 344 ms
84,804 KB |
testcase_03 | AC | 355 ms
84,764 KB |
testcase_04 | AC | 347 ms
84,528 KB |
testcase_05 | AC | 354 ms
84,712 KB |
testcase_06 | AC | 347 ms
85,100 KB |
testcase_07 | AC | 355 ms
85,240 KB |
testcase_08 | AC | 350 ms
85,064 KB |
testcase_09 | AC | 341 ms
84,856 KB |
testcase_10 | AC | 346 ms
85,048 KB |
testcase_11 | AC | 348 ms
84,892 KB |
testcase_12 | AC | 407 ms
86,004 KB |
testcase_13 | AC | 322 ms
83,048 KB |
testcase_14 | AC | 332 ms
84,344 KB |
testcase_15 | AC | 452 ms
111,872 KB |
testcase_16 | AC | 471 ms
116,484 KB |
testcase_17 | AC | 472 ms
113,604 KB |
testcase_18 | AC | 396 ms
119,296 KB |
testcase_19 | AC | 498 ms
115,544 KB |
testcase_20 | AC | 398 ms
115,100 KB |
ソースコード
import sys from typing import List def bottom_up_order(g: List[List[int]], root: int = 0): n = len(g) parent = [-1] * n bfs_order = [root] for u in bfs_order: for v in g[u]: if v != parent[u]: bfs_order.append(v) parent[v] = u return list(reversed(bfs_order)), parent def solve(n: int, g: List[List[int]]): m = n * (n + 1) // 2 denoms = [] vs, par = bottom_up_order(g) # size of subtrees sub = [0] * n for u in vs: # # of paths including {u} p_u = m sub[u] = 1 for v in g[u]: if v == par[u]: continue p_u -= sub[v] * (sub[v] + 1) // 2 # # of paths including {u, v} p_uv = sub[v] * (n - sub[v]) denoms.append(-(m - p_uv)) # ans -= m / (m - p_uv) sub[u] += sub[v] if par[u] != -1: sub_p = n - sub[u] p_u -= sub_p * (sub_p + 1) // 2 denoms.append(m - p_u) # ans += m / (m - p_u) inv_denoms = modinvs(denoms) return sum(inv_denoms) % P * m % P if __name__ == '__main__': P = 998244353 def modinv(v: int): return pow(v, P - 2, P) def modinvs(a: List[int]): prod = 1 for v in a: prod = prod * v % P prod_inv = modinv(prod) n = len(a) rprod = [0] * (n + 1) rprod[n] = 1 for i in reversed(range(n)): rprod[i] = rprod[i + 1] * a[i] % P inv_a = [0] * n lprod = 1 for i, v in enumerate(a): inv_a[i] = lprod * rprod[i + 1] % P * prod_inv % P lprod = lprod * v % P return inv_a answers = [] T = int(sys.stdin.readline().rstrip()) for _ in range(T): n = int(sys.stdin.readline().rstrip()) g = [[] for _ in range(n)] for _ in range(n - 1): u, v = map(int, sys.stdin.readline().rstrip().split()) u -= 1 v -= 1 g[u].append(v) g[v].append(u) answers.append(solve(n, g)) print('\n'.join(map(str, answers)))