結果
問題 | No.1124 Earthquake Safety |
ユーザー | maspy |
提出日時 | 2020-07-22 22:46:53 |
言語 | Python3 (3.12.2 + numpy 1.26.4 + scipy 1.12.0) |
結果 |
AC
|
実行時間 | 2,636 ms / 3,000 ms |
コード長 | 1,349 bytes |
コンパイル時間 | 156 ms |
コンパイル使用メモリ | 10,972 KB |
実行使用メモリ | 109,688 KB |
最終ジャッジ日時 | 2023-09-05 02:59:38 |
合計ジャッジ時間 | 94,360 ms |
ジャッジサーバーID (参考情報) |
judge13 / judge12 |
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 | 18 ms
8,136 KB |
testcase_01 | AC | 17 ms
8,068 KB |
testcase_02 | AC | 17 ms
8,132 KB |
testcase_03 | AC | 17 ms
8,208 KB |
testcase_04 | AC | 17 ms
8,204 KB |
testcase_05 | AC | 16 ms
8,136 KB |
testcase_06 | AC | 21 ms
8,440 KB |
testcase_07 | AC | 70 ms
11,600 KB |
testcase_08 | AC | 736 ms
38,764 KB |
testcase_09 | AC | 2,417 ms
102,164 KB |
testcase_10 | AC | 1,604 ms
109,688 KB |
testcase_11 | AC | 18 ms
8,140 KB |
testcase_12 | AC | 18 ms
8,128 KB |
testcase_13 | AC | 17 ms
8,080 KB |
testcase_14 | AC | 2,595 ms
100,332 KB |
testcase_15 | AC | 2,591 ms
100,268 KB |
testcase_16 | AC | 2,556 ms
100,492 KB |
testcase_17 | AC | 2,636 ms
100,424 KB |
testcase_18 | AC | 2,577 ms
100,416 KB |
testcase_19 | AC | 2,565 ms
100,276 KB |
testcase_20 | AC | 2,579 ms
100,216 KB |
testcase_21 | AC | 2,601 ms
100,604 KB |
testcase_22 | AC | 2,597 ms
100,496 KB |
testcase_23 | AC | 2,512 ms
103,296 KB |
testcase_24 | AC | 2,507 ms
103,304 KB |
testcase_25 | AC | 2,445 ms
104,180 KB |
testcase_26 | AC | 2,449 ms
102,360 KB |
testcase_27 | AC | 2,345 ms
102,808 KB |
testcase_28 | AC | 2,399 ms
102,792 KB |
testcase_29 | AC | 2,404 ms
103,560 KB |
testcase_30 | AC | 2,376 ms
103,872 KB |
testcase_31 | AC | 2,385 ms
105,396 KB |
testcase_32 | AC | 2,370 ms
105,540 KB |
testcase_33 | AC | 2,311 ms
109,684 KB |
testcase_34 | AC | 2,344 ms
109,436 KB |
testcase_35 | AC | 2,326 ms
96,116 KB |
testcase_36 | AC | 2,324 ms
97,044 KB |
testcase_37 | AC | 2,248 ms
95,340 KB |
testcase_38 | AC | 2,268 ms
96,448 KB |
testcase_39 | AC | 2,219 ms
94,916 KB |
testcase_40 | AC | 2,170 ms
95,556 KB |
testcase_41 | AC | 2,191 ms
94,604 KB |
testcase_42 | AC | 2,105 ms
95,432 KB |
testcase_43 | AC | 2,119 ms
95,756 KB |
testcase_44 | AC | 2,086 ms
93,160 KB |
testcase_45 | AC | 2,111 ms
93,416 KB |
testcase_46 | AC | 2,069 ms
95,132 KB |
testcase_47 | AC | 2,090 ms
93,328 KB |
testcase_48 | AC | 2,125 ms
93,664 KB |
testcase_49 | AC | 2,123 ms
93,096 KB |
testcase_50 | AC | 17 ms
8,092 KB |
testcase_51 | AC | 16 ms
8,208 KB |
testcase_52 | AC | 17 ms
8,052 KB |
testcase_53 | AC | 16 ms
8,200 KB |
testcase_54 | AC | 16 ms
8,016 KB |
testcase_55 | AC | 17 ms
8,084 KB |
testcase_56 | AC | 17 ms
8,196 KB |
testcase_57 | AC | 17 ms
8,156 KB |
ソースコード
import sys read = sys.stdin.buffer.read readline = sys.stdin.buffer.readline readlines = sys.stdin.buffer.readlines MOD = 10**9 + 7 inv2 = pow(2, MOD - 2, MOD) inv4 = inv2**2 % MOD def dfs_order(G, root=1): parent = [0] * (N + 1) order = [] stack = [root] while stack: x = stack.pop() order.append(x) for y in G[x]: if y == parent[x]: continue parent[y] = x stack.append(y) return parent, order N = int(readline()) m = map(int, read().split()) G = [[] for _ in range(N + 1)] for a, b in zip(m, m): G[a].append(b) G[b].append(a) root = 1 parent, order = dfs_order(G, root) mu1 = [0] * (N + 1) var1 = [0] * (N + 1) for v in order[::-1]: p = parent[v] mu1[v] += 1 mu1[v] %= MOD var1[v] %= MOD mu1[p] += inv2 * mu1[v] var1[p] += var1[v] * inv2 + mu1[v] * mu1[v] * inv4 mu2 = [0] * (N + 1) var2 = [0] * (N + 1) for v in order: mu2[v] = mu1[v] var2[v] = var1[v] if v == root: continue p = parent[v] mu = mu2[p] - mu1[v] * inv2 var = var2[p] - inv2 * var2[v] - mu1[v]**2 * inv4 mu2[v] += mu * inv2 var2[v] += mu * mu * inv4 + var * inv2 mu2[v] %= MOD var2[v] %= MOD ans = 0 for v in range(1, N+1): ans += mu2[v] ** 2 + var2[v] ans *= pow(2, N-1, MOD) print(ans % MOD)