[20250705] BOJ / P5 / 대기업 승범이네 / 권혁준

Author: oncsr

khj20006/202507/05 BOJ P5 대기업 승범이네.md

@@ -0,0 +1,104 @@
+```java
+import java.util.*;
+import java.io.*;
+
+class IOController {
+    BufferedReader br;
+    BufferedWriter bw;
+    StringTokenizer st;
+
+    public IOController() {
+        br = new BufferedReader(new InputStreamReader(System.in));
+        bw = new BufferedWriter(new OutputStreamWriter(System.out));
+        st = new StringTokenizer("");
+    }
+
+    String nextLine() throws Exception {
+        String line = br.readLine();
+        st = new StringTokenizer(line);
+        return line;
+    }
+
+    String nextToken() throws Exception {
+        while (!st.hasMoreTokens()) nextLine();
+        return st.nextToken();
+    }
+
+    int nextInt() throws Exception {
+        return Integer.parseInt(nextToken());
+    }
+
+    long nextLong() throws Exception {
+        return Long.parseLong(nextToken());
+    }
+
+    double nextDouble() throws Exception {
+        return Double.parseDouble(nextToken());
+    }
+
+    void close() throws Exception {
+        bw.flush();
+        bw.close();
+    }
+
+    void write(String content) throws Exception {
+        bw.write(content);
+    }
+
+}
+
+public class Main {
+
+    static IOController io;
+
+    //
+
+    static int N;
+    static int[] A;
+    static int[][] dp;
+    static List<Integer>[] V;
+
+    public static void main(String[] args) throws Exception {
+
+        io = new IOController();
+
+        init();
+        solve();
+
+        io.close();
+
+    }
+
+    public static void init() throws Exception {
+
+        N = io.nextInt();
+        A = new int[N+1];
+        V = new List[N+1];
+        for(int i=1;i<=N;i++) V[i] = new ArrayList<>();
+        for(int i=2;i<=N;i++) V[io.nextInt()].add(i);
+        for(int i=1;i<=N;i++) A[i] = io.nextInt();
+        dp = new int[N+1][2];
+
+    }
+
+    static void solve() throws Exception {
+
+        dfs(1);
+        io.write(Math.max(dp[1][0], dp[1][1]) + "\n");
+
+    }
+
+    static void dfs(int n) {
+        for(int i:V[n]) {
+            dfs(i);
+            dp[n][0] += Math.max(dp[i][0], dp[i][1]);
+        }
+        int max = Integer.MIN_VALUE;
+        for(int i:V[n]) {
+            max = Math.max(max, -Math.max(dp[i][0], dp[i][1]) + dp[i][0] + A[i] * A[n]);
+        }
+        dp[n][1] = dp[n][0] + max;
+    }
+
+}
+```