From 3266ee94ccc982cb1821111ee84e215196be8f50 Mon Sep 17 00:00:00 2001
From: Baoshuo <i@baoshuo.ren>
Date: Sun, 19 Feb 2023 10:20:14 +0800
Subject: [PATCH] =?UTF-8?q?P3354=20[IOI2005]Riv=20=E6=B2=B3=E6=B5=81?=
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https://www.luogu.com.cn/record/102483854
---
 Luogu/P3354/P3354.cpp | 63 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 63 insertions(+)
 create mode 100644 Luogu/P3354/P3354.cpp

diff --git a/Luogu/P3354/P3354.cpp b/Luogu/P3354/P3354.cpp
new file mode 100644
index 00000000..44e7d23a
--- /dev/null
+++ b/Luogu/P3354/P3354.cpp
@@ -0,0 +1,63 @@
+#include <iostream>
+#include <vector>
+
+using std::cin;
+using std::cout;
+const char endl = '\n';
+
+const int N = 105;
+
+int n, k, w[N], v[N], d[N], dis[N];
+int f[N][2][N][N];
+std::vector<int> g[N], st;
+
+void dfs(int u) {
+    st.emplace_back(u);
+
+    for (int v : g[u]) {
+        dis[v] = dis[u] + d[v];
+
+        dfs(v);
+
+        for (int t : st) {
+            for (int i = k; i >= 0; i--) {
+                f[u][0][t][i] += f[v][0][t][0];
+                f[u][1][t][i] += f[v][0][u][0];
+
+                for (int j = 1; j <= i; j++) {
+                    f[u][0][t][i] = std::min(f[u][0][t][i], f[v][0][t][j] + f[u][0][t][i - j]);
+                    f[u][1][t][i] = std::min(f[u][1][t][i], f[v][0][u][j] + f[u][1][t][i - j]);
+                }
+            }
+        }
+    }
+
+    for (int t : st) {
+        for (int i = k; i; i--) {
+            f[u][0][t][i] = std::min(f[u][0][t][i] + w[u] * (dis[u] - dis[t]), f[u][1][t][i - 1]);
+        }
+
+        f[u][0][t][0] += w[u] * (dis[u] - dis[t]);
+    }
+
+    st.pop_back();
+}
+
+int main() {
+    std::ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    cin >> n >> k;
+
+    for (int i = 1; i <= n; i++) {
+        cin >> w[i] >> v[i] >> d[i];
+
+        g[v[i]].emplace_back(i);
+    }
+
+    dfs(0);
+
+    cout << f[0][0][0][k] << endl;
+
+    return 0;
+}