#include <bits/stdc++.h>
 
using namespace std;
 
#define DEBUG(x) cerr<<#x<<": "<<x<<endl;
#define DEBUG_VEC(v) cerr<<#v<<":";for(int i=0;i<v.size();i++) cerr<<" "<<v[i]; cerr<<endl;
#define DEBUG_MAT(v) cerr<<#v<<endl;for(int i=0;i<v.size();i++){for(int j=0;j<v[i].size();j++) {cerr<<v[i][j]<<" ";}cerr<<endl;}
typedef long long ll;
#define int ll
 
#define vi vector<int>
#define vl vector<ll>
#define vii vector< vector<int> >
#define vll vector< vector<ll> >
#define vs vector<string>
#define pii pair<int,int>
#define pis pair<int,string>
#define psi pair<string,int>
#define pll pair<ll,ll>
template<class S, class T> pair<S, T> operator+(const pair<S, T> &s, const pair<S, T> &t) { return pair<S, T>(s.first + t.first, s.second + t.second); }
template<class S, class T> pair<S, T> operator-(const pair<S, T> &s, const pair<S, T> &t) { return pair<S, T>(s.first - t.first, s.second - t.second); }
template<class S, class T> ostream& operator<<(ostream& os, pair<S, T> p) { os << "(" << p.first << ", " << p.second << ")"; return os; }
#define X first
#define Y second
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define rep1(i,n) for(int i=1;i<=(int)(n);i++)
#define rrep(i,n) for(int i=(int)(n)-1;i>=0;i--)
#define rrep1(i,n) for(int i=(int)(n);i>0;i--)
#define REP(i,a,b) for(int i=a;i<b;i++)
#define in(x, a, b) (a <= x && x < b)
#define all(c) c.begin(),c.end()
template<class T> bool chmax(T &a, const T &b) { if (a<b) { a = b; return 1; } return 0; }
template<class T> bool chmin(T &a, const T &b) { if (a>b) { a = b; return 1; } return 0; }
#define UNIQUE(v) v.erase(std::unique(v.begin(), v.end()), v.end());
const ll inf = 1000000001;
const ll INF = (ll)1e18 + 1;
const long double pi = 3.1415926535897932384626433832795028841971L;
#define Sp(p) cout<<setprecision(25)<< fixed<<p<<endl;
// int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};
// int dx2[8] = { 1,1,0,-1,-1,-1,0,1 }, dy2[8] = { 0,1,1,1,0,-1,-1,-1 };
vi dx = {1, 0, -1, 0}, dy = {0, 1, 0, -1};
// vi dx2 = { 1,1,0,-1,-1,-1,0,1 }, dy2 = { 0,1,1,1,0,-1,-1,-1 };
#define fio() cin.tie(0); ios::sync_with_stdio(false);
const ll MOD = 1000000007;
// const ll MOD = 998244353;
// #define mp make_pair
//#define endl '\n'

const int N = 101234;
vl a(N), b(N);
vii G(N);

pll dfs(int now, int par) {
    using P = pair<int, pll>;
    vector<P> ch;
    for (int v: G[now]) {
        if (v == par) continue;
        ch.push_back({v, dfs(v, now)});
    }
    pll res(a[now], 0);
    rep (i, ch.size()) {
        pll score = ch[i].second;
        int v = ch[i].first;
        res.first += max(score.first, score.second);
        res.second += max(score.first, score.second + b[v] + b[now]);
    }
    return res;
}

signed main() {
    int n;
    cin >> n;
    rep (i, n) cin >> a[i];
    rep (i, n) cin >> b[i];

    rep (i, n - 1) {
        int u, v;
        cin >> u >> v;
        u--; v--;
        G[u].push_back(v);
        G[v].push_back(u);
    }
    pii res = dfs(0, -1);
    cout << max(res.first, res.second) << endl;
}

// vector<double> fact(111111);

// void solve() {
//     int n, m, k;
//     cin >> n >> m >> k;
//     double f = m * fact[n] / (fact[k] * fact[n - k]);
//     double s = (n - k + 1) * pow(m, k);
//     DEBUG(make_pair(f, s));
//     if (f > s) cout << "Straight" << endl;
//     else cout << "Flush" << endl;
// }

// signed main() {
//     fio();
//     fact[0] = 1;
//     rep (i, 111100) {
//         fact[i + 1] = fact[i] * (i + 1);
//     }

//     int q;
//     cin >> q;
//     while (q--) solve();
// }