結果
問題 | No.1333 Squared Sum |
ユーザー | toyuzuko |
提出日時 | 2021-04-17 23:33:25 |
言語 | PyPy3 (7.3.15) |
結果 |
AC
|
実行時間 | 1,659 ms / 2,000 ms |
コード長 | 2,703 bytes |
コンパイル時間 | 437 ms |
コンパイル使用メモリ | 86,820 KB |
実行使用メモリ | 216,044 KB |
最終ジャッジ日時 | 2023-09-17 07:23:17 |
合計ジャッジ時間 | 41,928 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 | 72 ms
71,400 KB |
testcase_01 | AC | 73 ms
71,164 KB |
testcase_02 | AC | 73 ms
70,976 KB |
testcase_03 | AC | 1,461 ms
200,560 KB |
testcase_04 | AC | 1,659 ms
200,912 KB |
testcase_05 | AC | 1,515 ms
200,784 KB |
testcase_06 | AC | 1,527 ms
201,952 KB |
testcase_07 | AC | 1,444 ms
201,788 KB |
testcase_08 | AC | 1,492 ms
203,876 KB |
testcase_09 | AC | 1,500 ms
200,728 KB |
testcase_10 | AC | 1,478 ms
201,684 KB |
testcase_11 | AC | 1,477 ms
201,136 KB |
testcase_12 | AC | 1,512 ms
203,900 KB |
testcase_13 | AC | 1,073 ms
210,632 KB |
testcase_14 | AC | 1,562 ms
211,948 KB |
testcase_15 | AC | 1,574 ms
213,052 KB |
testcase_16 | AC | 74 ms
71,304 KB |
testcase_17 | AC | 76 ms
71,412 KB |
testcase_18 | AC | 73 ms
71,188 KB |
testcase_19 | AC | 74 ms
71,392 KB |
testcase_20 | AC | 74 ms
71,268 KB |
testcase_21 | AC | 74 ms
71,012 KB |
testcase_22 | AC | 74 ms
71,300 KB |
testcase_23 | AC | 74 ms
71,140 KB |
testcase_24 | AC | 73 ms
71,332 KB |
testcase_25 | AC | 72 ms
71,068 KB |
testcase_26 | AC | 1,528 ms
194,592 KB |
testcase_27 | AC | 1,508 ms
195,860 KB |
testcase_28 | AC | 1,531 ms
195,184 KB |
testcase_29 | AC | 1,103 ms
193,488 KB |
testcase_30 | AC | 761 ms
130,944 KB |
testcase_31 | AC | 523 ms
108,028 KB |
testcase_32 | AC | 980 ms
154,012 KB |
testcase_33 | AC | 816 ms
137,048 KB |
testcase_34 | AC | 1,234 ms
177,040 KB |
testcase_35 | AC | 999 ms
153,556 KB |
testcase_36 | AC | 690 ms
125,208 KB |
testcase_37 | AC | 667 ms
123,104 KB |
testcase_38 | AC | 752 ms
132,760 KB |
testcase_39 | AC | 1,074 ms
163,780 KB |
testcase_40 | AC | 1,024 ms
214,784 KB |
testcase_41 | AC | 1,159 ms
216,044 KB |
testcase_42 | AC | 1,120 ms
213,804 KB |
testcase_43 | AC | 925 ms
212,416 KB |
ソースコード
class Tree(): def __init__(self, n): self.n = n self.tree = [[] for _ in range(n)] self.cost = dict() self.root = None def add_edge(self, u, v, c): if u > v: u, v = v, u self.tree[u].append(v) self.tree[v].append(u) self.cost[u * self.n + v] = c def get_cost(self, u, v): if u < v: return self.cost[u * self.n + v] else: return self.cost[v * self.n + u] def set_root(self, r=0): self.root = r self.par = [None] * self.n self.ord = [r] stack = [r] while stack: v = stack.pop() for adj in self.tree[v]: if self.par[v] == adj: continue 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 in self.tree[v]: if self.par[v] == adj: continue lt[adj] = tl self.w = self.get_cost(v, adj) tl = op(tl, dp[adj]) for adj in self.tree[v][::-1]: if self.par[v] == adj: continue rt[adj] = tr self.w = self.get_cost(v, adj) tr = op(tr, dp[adj]) dp[v] = tr for v in self.ord: if v == self.root: continue p = self.par[v] if p != self.root: pp = self.par[p] self.w = self.get_cost(p, pp) inv[v] = op(merge(lt[v], rt[v]), inv[p]) else: inv[v] = merge(lt[v], rt[v]) self.w = self.get_cost(v, p) dp[v] = op(dp[v], inv[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) e = (1, 0, 0) def op(p, c): ps, pd, pds = p cs, cd, cds = c size = ps + cs w = t.w dist = pd + cd + w * cs dsq = (pds + cds + w**2 * cs + 2 * w * cd) % MOD return size, dist, dsq id = (0, 0, 0) def merge(lt, rt): ls, ld, lds = lt rs, rd, rds = rt size = ls + rs - 1 dist = ld + rd dsq = (lds + rds) % MOD return size, dist, dsq dp = t.rerooting(op, e, merge, id) res = 0 for size, dist, dsq in dp: res += dsq res %= MOD print(res * pow(2, MOD - 2, MOD) % MOD)