'commit'

TangDou/Topic/HuanGenDp/CF1324F.cpp

@@ -0,0 +1,54 @@
+#include <bits/stdc++.h>
+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;
+}

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
 
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