結果
問題 | No.1221 木 *= 3 |
ユーザー |
|
提出日時 | 2020-09-04 22:08:29 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 137 ms / 2,000 ms |
コード長 | 2,069 bytes |
コンパイル時間 | 2,351 ms |
コンパイル使用メモリ | 204,380 KB |
最終ジャッジ日時 | 2025-01-14 05:48:38 |
ジャッジサーバーID (参考情報) |
judge3 / judge5 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 4 |
other | AC * 18 |
コンパイルメッセージ
main.cpp: In function ‘int main()’: main.cpp:58:10: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result] 58 | scanf("%d", &n); | ~~~~~^~~~~~~~~~ main.cpp:60:14: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result] 60 | scanf("%d", a + i); | ~~~~~^~~~~~~~~~~~~ main.cpp:62:14: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result] 62 | scanf("%d", b + i); | ~~~~~^~~~~~~~~~~~~ main.cpp:65:14: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result] 65 | scanf("%d%d", &u, &v); | ~~~~~^~~~~~~~~~~~~~~~
ソースコード
#include <bits/stdc++.h>const int maxn = 2e5 + 3;using ll = long long;int n, a[maxn], b[maxn], p[maxn];std::vector<int> E[maxn], c[maxn];ll dp[maxn][2][2];void dfs(int u) {for(auto &&v : E[u]) {if(v == p[u])continue;p[v] = u;dfs(v);c[u].push_back(v);}ll au = a[u], bu = b[u];{{ll &ansP = dp[u][1][1], &ansN = dp[u][1][0], dps = 0;std::vector<ll> tr;for(auto &&v : c[u]) {dps += dp[v][0][1];tr.push_back(dp[v][1][1] - dp[v][0][1]);}std::sort(tr.rbegin(), tr.rend());ll dpp = 0;ansP = dps + dpp + bu * 1ll;ansN = dps + dpp + bu * 0ll;for(int j = 0; j < c[u].size(); ++j) {dpp += tr[j];ansP = std::max(ansP, dps + dpp + bu * ll(j + 2ll));ansN = std::max(ansN, dps + dpp + bu * ll(j + 1ll));}}{ll &ansP = dp[u][0][1], &ansN = dp[u][0][0], dps = 0;std::vector<ll> tr;for(auto &&v : c[u]) {dps += dp[v][0][0];tr.push_back(dp[v][1][0] - dp[v][0][0]);}std::sort(tr.rbegin(), tr.rend());ll dpp = 0;ansP = dps + dpp + au;ansN = dps + dpp + au;for(int j = 0; j < c[u].size(); ++j) {dpp += tr[j];ansP = std::max(ansP, dps + dpp + au);ansN = std::max(ansN, dps + dpp + au);}}}}int main() {scanf("%d", &n);for(int i = 1; i <= n; ++i)scanf("%d", a + i);for(int i = 1; i <= n; ++i)scanf("%d", b + i);for(int i = 0; i < n - 1; ++i) {int u, v;scanf("%d%d", &u, &v);E[u].push_back(v);E[v].push_back(u);}dfs(1);ll ans = dp[1][0][0];for(int i = 0; i < 2; ++i)ans = std::max(ans, dp[1][i][0]);printf("%lld\n", ans);return 0;}