#include<iostream>
#include<string>
#include<cstring>
#include<algorithm>
#include<vector>
#include<iomanip>
#include<math.h>
#include<complex>
#include<queue>
#include<deque>
#include<stack>
#include<map>
#include<set>
#include<bitset>
#include<functional>
#include<assert.h>
#include<numeric>
using namespace std;
#define REP(i,m,n) for(int i=(int)(m) ; i < (int) (n) ; ++i )
#define rep(i,n) REP(i,0,n)
using ll = long long;
const int inf=1e9+7;
const ll longinf=1LL<<60 ;
const ll mod=1e9+7 ;
#define PI 3.141592653589793

vector<int> to[101010];
ll dp[101010][2];
ll c[101010], b[101010];

void DFS(int a, int p){
  vector<pair<ll, int>> kurabe;
  dp[a][0] = c[a];
  for(auto k: to[a]){
    if(k==p) continue;
    DFS(k, a);
    kurabe.push_back({dp[k][1]+b[a]+b[k]-dp[k][0], k});
    if(dp[k][1]>dp[k][0]) dp[a][0]+=dp[k][1];
    else dp[a][0]+=dp[k][0];
    dp[a][1]+=dp[k][0];
  }
  sort(kurabe.begin(), kurabe.end(), greater<>());
  ll nyan = dp[a][1];
  rep(i, kurabe.size()){
    if(kurabe[i].first>0) dp[a][1]+=kurabe[i].first;
  }
}


int main(){
  int n; cin >> n; 
  rep(i, n) cin >> c[i];
  rep(i, n) cin >> b[i];
  rep(i, n-1){
    int u, v; cin >> u >> v; u--; v--;
    to[u].push_back(v); to[v].push_back(u);
  }
  DFS(0, -1);
  cout << max(dp[0][0], dp[0][1]) << endl;
  //cout << dp[0][1] << endl;
}