結果
問題 | No.1333 Squared Sum |
ユーザー | toyuzuko |
提出日時 | 2021-04-18 00:17:35 |
言語 | PyPy3 (7.3.15) |
結果 |
AC
|
実行時間 | 1,315 ms / 2,000 ms |
コード長 | 2,431 bytes |
コンパイル時間 | 280 ms |
コンパイル使用メモリ | 86,768 KB |
実行使用メモリ | 208,460 KB |
最終ジャッジ日時 | 2023-09-17 07:27:44 |
合計ジャッジ時間 | 36,227 ms |
ジャッジサーバーID (参考情報) |
judge14 / judge15 |
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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 | 76 ms
70,864 KB |
testcase_01 | AC | 74 ms
70,692 KB |
testcase_02 | AC | 75 ms
71,084 KB |
testcase_03 | AC | 1,229 ms
194,780 KB |
testcase_04 | AC | 1,284 ms
199,488 KB |
testcase_05 | AC | 1,241 ms
200,272 KB |
testcase_06 | AC | 1,277 ms
199,496 KB |
testcase_07 | AC | 1,261 ms
198,756 KB |
testcase_08 | AC | 1,266 ms
198,236 KB |
testcase_09 | AC | 1,271 ms
199,128 KB |
testcase_10 | AC | 1,312 ms
194,824 KB |
testcase_11 | AC | 1,278 ms
199,016 KB |
testcase_12 | AC | 1,287 ms
198,420 KB |
testcase_13 | AC | 888 ms
190,608 KB |
testcase_14 | AC | 1,295 ms
189,192 KB |
testcase_15 | AC | 1,300 ms
188,528 KB |
testcase_16 | AC | 73 ms
70,884 KB |
testcase_17 | AC | 75 ms
71,040 KB |
testcase_18 | AC | 76 ms
71,096 KB |
testcase_19 | AC | 74 ms
70,712 KB |
testcase_20 | AC | 73 ms
70,852 KB |
testcase_21 | AC | 72 ms
71,008 KB |
testcase_22 | AC | 73 ms
70,880 KB |
testcase_23 | AC | 75 ms
70,864 KB |
testcase_24 | AC | 73 ms
71,012 KB |
testcase_25 | AC | 72 ms
71,196 KB |
testcase_26 | AC | 1,283 ms
187,500 KB |
testcase_27 | AC | 1,310 ms
188,228 KB |
testcase_28 | AC | 1,315 ms
188,744 KB |
testcase_29 | AC | 876 ms
188,024 KB |
testcase_30 | AC | 572 ms
125,900 KB |
testcase_31 | AC | 392 ms
105,044 KB |
testcase_32 | AC | 785 ms
147,884 KB |
testcase_33 | AC | 656 ms
133,336 KB |
testcase_34 | AC | 1,019 ms
170,928 KB |
testcase_35 | AC | 800 ms
148,096 KB |
testcase_36 | AC | 534 ms
118,824 KB |
testcase_37 | AC | 535 ms
120,864 KB |
testcase_38 | AC | 597 ms
127,440 KB |
testcase_39 | AC | 899 ms
158,216 KB |
testcase_40 | AC | 1,045 ms
208,244 KB |
testcase_41 | AC | 1,069 ms
207,096 KB |
testcase_42 | AC | 962 ms
208,460 KB |
testcase_43 | AC | 1,037 ms
206,924 KB |
ソースコード
class Tree(): def __init__(self, n): self.n = n self.tree = [[] for _ in range(n)] self.root = None def add_edge(self, u, v, c): if u > v: u, v = v, u self.tree[u].append((v, c)) self.tree[v].append((u, c)) def set_root(self, r=0): self.root = r self.par = [None] * self.n self.ord = [r] self.cost = [0] * N stack = [r] while stack: v = stack.pop() for adj, cost in self.tree[v]: if self.par[v] == adj: continue self.cost[adj] = cost self.par[adj] = v self.ord.append(adj) stack.append(adj) def rerooting(self, op, e, merge, id): if self.root is None: self.set_root() dp = [e] * self.n lt = [id] * self.n rt = [id] * self.n inv = [id] * self.n for v in self.ord[::-1]: tl = tr = e for adj, cost in self.tree[v]: if self.par[v] == adj: continue lt[adj] = tl tl = op(tl, dp[adj], cost) for adj, cost in self.tree[v][::-1]: if self.par[v] == adj: continue rt[adj] = tr tr = op(tr, dp[adj], cost) dp[v] = tr for v in self.ord: if v == self.root: continue p = self.par[v] inv[v] = op(merge(lt[v], rt[v]), inv[p], self.cost[p]) dp[v] = op(dp[v], inv[v], self.cost[v]) return dp import io, os input = io.BytesIO(os.read(0, os.fstat(0).st_size)).readline MOD = 1000000007 N = int(input()) t = Tree(N) for _ in range(N - 1): u, v, w = map(int, input().split()) u -= 1; v -= 1 t.add_edge(u, v, w) def op(p, v, d): p_size, p_dist, p_square = p v_size, v_dist, v_square = v size = p_size + v_size dist = (p_dist + v_dist + d * v_size) % MOD square = (p_square + v_square + d**2 * v_size + 2 * d * v_dist) % MOD return size, dist, square def merge(lt, rt): l_size, l_dist, l_square = lt r_size, r_dist, r_square = rt size = l_size + r_size - 1 dist = (l_dist + r_dist) % MOD square = (l_square + r_square) % MOD return size, dist, square dp = t.rerooting(op, (1, 0, 0), merge, (0, 0, 0)) res = 0 for size, dist, square in dp: res += square res %= MOD print(res * pow(2, MOD - 2, MOD) % MOD)