#include "tree.h"
#include <bits/stdc++.h>
#define rep(i,j,k) for(int i=(j);i<=(k);i++)
#define per(i,j,k) for(int i=(j);i>=(k);i--)
#define uint unsigned int
#define ll long long
#define ull unsigned long long
#define db double
#define ldb long double
#define pii pair<int,int>
#define pll pair<ll,ll>
#define mkp make_pair
#define eb emplace_back
#define SZ(S) (int)S.size()
//#define mod 998244353
//#define mod 1000000007
#define inf 0x3f3f3f3f
#define linf 0x3f3f3f3f3f3f3f3f
using namespace std;

template <class T>
void chkmax(T &x,T y){
  if(x < y) x = y;
}

template <class T>
void chkmin(T &x,T y){
  if(x > y) x = y;
}

inline int popcnt(int x){
  return __builtin_popcount(x);
}

inline int ctz(int x){
  return __builtin_ctz(x);
}


/*ll power(ll p,int k = mod - 2){
  ll ans = 1;
  while(k){
    if(k % 2 == 1) ans = ans * p % mod;
    p = p * p % mod;
    k /= 2; 
  }
  return ans;
}*/

int n,m;
int fa[200005],w[200005];
vector <int> son[200005];

void init(std::vector<int> _P, std::vector<int> _W) {
    n = SZ(_P);
    rep(u,2,n) fa[u] = _P[u - 1] + 1;
    rep(u,2,n) son[fa[u]].eb(u);
    rep(u,1,n){
        w[u] = _W[u - 1];
        chkmax(m,w[u]);
    }
//    cerr << "m=" << m << endl;
}
int L,R;
ll dp[200005][25];
void slv(int u){
    for(int v:son[u]){
        rep(i,0,2 * m){
            ll Mx = -linf;
            rep(j,0,2 * m){
                if(i > j) chkmax(Mx,dp[v][j] + 1ll * L * (i - j));
                else chkmax(Mx,dp[v][j] - 1ll * R * (j - i));
            }
            dp[u][i] += Mx;
        }
    }
}

ll query(int _L,int _R) {
    L = _L;R = _R;
    rep(u,1,n) fill(dp[u],dp[u] + 2 * m + 1,0);
    per(u,n,1) slv(u);
    ll answer = 0;
    rep(i,0,m) chkmax(answer,dp[1][i] + 1ll * (m - i) * L);
    rep(i,m,2 * m) chkmax(answer,dp[1][i] - 1ll * (i - m) * R);
    return answer;
}
/*
g++ grader.cpp tree.cpp -o grader.exe -Wall -Wshadow -O2 -std=c++14
*/