From aaec68c0f45bf5233b29a541b032ba54ae97990c Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=E9=BB=84=E6=B5=B7?= <10402852@qq.com> Date: Wed, 10 Jan 2024 08:42:46 +0800 Subject: [PATCH] 'commit' --- TangDou/Topic/HuanGenDp/CF1324F.cpp | 54 ++++++++++++++++++++++++++ TangDou/Topic/【换根】dfs专题.md | 3 +- 2 files changed, 56 insertions(+), 1 deletion(-) create mode 100644 TangDou/Topic/HuanGenDp/CF1324F.cpp diff --git a/TangDou/Topic/HuanGenDp/CF1324F.cpp b/TangDou/Topic/HuanGenDp/CF1324F.cpp new file mode 100644 index 0000000..8917e1a --- /dev/null +++ b/TangDou/Topic/HuanGenDp/CF1324F.cpp @@ -0,0 +1,54 @@ +#include +using namespace std; +const int N = 200010, M = N << 1; + +int n, a[N], f1[N], f2[N]; +int head[N << 1], nxt[N << 1], to[N << 1], tot = 0; +void add(int u, int v) { + to[++tot] = v; + nxt[tot] = head[u]; + head[u] = tot; +} + +void dfs1(int u, int fa) { + if (a[u]) + f1[u] = 1; + else + f1[u] = -1; + + for (int i = head[u]; i; i = nxt[i]) { + int v = to[i]; + if (v == fa) + continue; + dfs1(v, u); + f1[u] += max(f1[v], 0); + } +} + +void dfs2(int u, int fa) { + for (int i = head[u]; i; i = nxt[i]) { + int v = to[i]; + if (v == fa) + continue; + f2[v] = max(f2[u] + f1[u] - max(f1[v], 0), 0); + dfs2(v, u); + } +} +int main() { + cin >> n; + + for (int i = 1; i <= n; i++) cin >> a[i]; + + for (int i = 1; i <= n - 1; i++) { + int a, b; + cin >> a >> b; + add(a, b), add(b, a); + } + + dfs1(1, 1); + + dfs2(1, 1); + for (int i = 1; i <= n; i++) printf("%d ", f1[i] + f2[i]); + + return 0; +} diff --git a/TangDou/Topic/【换根】dfs专题.md b/TangDou/Topic/【换根】dfs专题.md index e7135c6..31cbce2 100644 --- a/TangDou/Topic/【换根】dfs专题.md +++ b/TangDou/Topic/【换根】dfs专题.md @@ -567,8 +567,9 @@ signed main() { ``` +#### [$CF1324F$.$Maximum$ $White$ $Subtree$](https://codeforces.com/problemset/problem/1324/F) +![](https://dsideal.obs.cn-north-1.myhuaweicloud.com/HuangHai/BlogImages/202401100839763.png) -CF1324F.Maximum White Subtree [USACO12FEB]Nearby Cows G