#include <bits/stdc++.h>  // clang-format off
#define pb push_back
#define eb emplace_back
#define fi first
#define se second
#define each(x,v) for(auto& x : v)
#define all(v) (v).begin(),(v).end()
#define sz(v) ((int)(v).size())
#define ini(...) int __VA_ARGS__; in(__VA_ARGS__)
#define inl(...) long long __VA_ARGS__; in(__VA_ARGS__)
#define ins(...) string __VA_ARGS__; in(__VA_ARGS__)
#define inc(...) char __VA_ARGS__; in(__VA_ARGS__)
#define in2(s,t)     rep(i,sz(s)){in(s[i] , t[i]);}
#define in3(s,t,u)   rep(i,sz(s)){in(s[i] , t[i] , u[i]);}
#define in4(s,t,u,v) rep(i,sz(s)){in(s[i] , t[i] , u[i] , v[i]);}
#ifdef ONLINE_JUDGE
  #define rep(i,N) for(int i = 0; i < (int)(N); i++)
  #define repr(i,N) for(int i = (int)(N) - 1; i >= 0; i--)
  #define rep1(i,N) for(int i = 1; i <= (int)(N) ; i++)
  #define repr1(i,N) for(int i = (N) ; (int)(i) > 0 ; i--)
#else
  #define rep(i,N) for(long long i = 0; i < (long long)(N); i++)
  #define repr(i,N) for(long long i = (long long)(N) - 1; i >= 0; i--)
  #define rep1(i,N) for(long long i = 1; i <= (long long)(N) ; i++)
  #define repr1(i,N) for(long long i = (N) ; (long long)(i) > 0 ; i--)
#endif
using namespace std; void solve();
using ll = long long; template<class T = ll> using V = vector<T>;
using vi = V<int>; using vl = V<>; using vvi = V< V<int> >;
using vd = V<double>; using vs = V<string>; using vvl = V< V<> >;
constexpr int inf = 1001001001; constexpr ll infLL = (1LL << 61) - 1;
template<typename T, typename U> inline bool amin(T &x, U y) { return (y < x) ? (x = y, true) : false; }
template<typename T, typename U> inline bool amax(T &x, U y) { return (x < y) ? (x = y, true) : false; }
template<typename T,typename U>ll ceil(T a,U b){return (a + b - 1) / b;}
template<typename T, typename U> ostream& operator <<(ostream& os, const pair<T, U> &p) { os << p.first << " " << p.second; return os; }
template<typename T, typename U> istream& operator >>(istream& is, pair<T, U> &p) { is >> p.first >> p.second; return is; }
template<typename T> ostream& operator <<(ostream& os, const vector<T> &v) { int s = (int)v.size(); for(int i=0;i<s;i++) os << (i ? " " : "") << v[i]; return os; }
template<typename T> istream& operator >>(istream& is, vector<T> &v) { for(auto &x : v) is >> x; return is; }
void in(){} template <typename T,class... U> void in(T &t,U &...u){ cin >> t; in(u...);}
void out(){cout << "\n";} template <typename T,class... U> void out(const T &t,const U &...u){ cout << t; if(sizeof...(u)) cout << " "; out(u...);}
template<typename T>void die(T x){out(x); exit(0);}

#ifdef NyaanDebug
  #include "NyaanDebug.h"
  #define trc(...) do { cerr << #__VA_ARGS__ << " = "; dbg_out(__VA_ARGS__);} while(0)
  #define trca(v,N) do { cerr << #v << " = "; array_out(v , N);} while(0)
  #define trcc(v) do { cerr << "name : " << #v << "\n"; int cnt = 0; each(x , v){cerr << (cnt++) << " : "; trc(x); } } while(0)
#else
  #define trc(...)
  #define trca(...)
  #define trcc(...)
  int main(){solve();}
#endif

constexpr ll TEN(int n){ll ret=1,x=10;while(n){if(n&1)ret*=x;x*=x;n>>=1;}return ret;}
#define mem(a, val) memset(a, val, sizeof(a))

struct IoSetupNya {IoSetupNya() { cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(15); cerr << fixed << setprecision(7);} } iosetupnya;
using P = pair<ll,ll>; using vp = V<P>;
constexpr int MOD = /** 1000000007; //*/ 998244353;
// clang-format on
////////////////////////////////////////////////////

template <typename T>
struct edge {
  int src, to;
  T cost;

  edge(int to, T cost) : src(-1), to(to), cost(cost) {}
  edge(int src, int to, T cost) : src(src), to(to), cost(cost) {}

  edge &operator=(const int &x) {
    to = x;
    return *this;
  }

  operator int() const { return to; }
};
template <typename T>
using Edges = vector<edge<T> >;
template <typename T>
using WeightedGraph = vector<Edges<T> >;
using UnweightedGraph = vector<vector<int> >;

// Input of (Unweighted) Graph
UnweightedGraph graph(int N, int M = -1, bool is_directed = false,
                      bool is_1origin = true) {
  UnweightedGraph g(N);
  if (M == -1) M = N - 1;
  for (int _ = 0; _ < M; _++) {
    int x, y;
    cin >> x >> y;
    if (is_1origin) x--, y--;
    g[x].pb(y);
    if (!is_directed) g[y].pb(x);
  }
  return g;
}

// Input of Weighted Graph
template <typename T>
WeightedGraph<T> wgraph(int N, int M = -1, bool is_directed = false,
                        bool is_1origin = true) {
  WeightedGraph<T> g(N);
  if (M == -1) M = N - 1;
  for (int _ = 0; _ < M; _++) {
    int x, y;
    cin >> x >> y;
    T c;
    cin >> c;
    if (is_1origin) x--, y--;
    g[x].eb(x, y, c);
    if (!is_directed) g[y].eb(y, x, c);
  }
  return g;
}

// Depth of Rooted Tree
// unvisited nodes : d = -1
vector<int> Depth(UnweightedGraph &g, int start = 0) {
  vector<int> d(g.size(), -1);
  auto dfs = [&](auto rec, int cur, int par = -1) -> void {
    d[cur] = par == -1 ? 0 : d[par] + 1;
    each(dst, g[cur]) {
      if (dst == par) continue;
      rec(rec, dst, cur);
    }
  };
  dfs(dfs, start);
  return d;
}

// Diameter of Tree
pair<int, int> Diameter(UnweightedGraph &g, int start = 0) {
  auto d = Depth(g, start);
  int u = max_element(begin(d), end(d)) - begin(d);
  d = Depth(g, u);
  int v = max_element(begin(d), end(d)) - begin(d);
  return make_pair(u, v);
}

void solve(){
  ini(N);
  auto g = graph(N);

  vl a(N),b(N); in(a,b);

  // 部分木の個数
  vl num(N);
  auto efs = [&](auto rec,int cur,int par = -1) -> ll{
    ll ret = 1;
    each(c , g[cur]){
      if(par == c) continue;
      ret += rec(rec , c , cur);
    }
    return num[cur] = ret;
  };
  efs(efs , 0);

  ll ans = 0;
  auto dfs = [&](auto rec,int cur,int par = -1) -> ll{
    
    vp chd;
    each(dst , g[cur]){
      if(dst == par) continue;
      chd.eb(rec(rec , dst , cur) , dst);
    }
    trc(cur , ans , chd , a[cur] , b[cur]);

    if((int)chd.size() != 0){
      ll ma = max_element(all(chd)) -> first;
      // ma回押す
      ans += ma;
      each(c , chd){
        a[cur] -= ma;
        ans += (ma - c.first) * (num[c.second]);
        a[cur] += ma - c.first;
        //a[par] += ma;
      }
      if(par != -1){
        a[cur] -= ma;
        a[par] += ma;
      }
    }
    if(par == -1){
      assert(a[cur] == b[cur]);
      return 0;
    }
    trc(a[cur] , b[cur]);
    if(a[cur] >= b[cur]){
        ll val = a[cur] - b[cur];
        ans += val * num[cur];
        a[par] += val;
        a[cur] -= val;
        return 0;
      }
    else return b[cur] - a[cur];
  };
  dfs(dfs , 0);

  out(ans);
}


Measured memory_bytes: 25204