#include <iostream>
#include <iomanip>
#include <algorithm>
#include <assert.h>
#include <complex>
#include <utility>
#include <vector>
#include <string>
#include <stack>
#include <queue>
#include <tuple>
#include <cmath>
#include <bitset>
#include <cctype>
#include <set>
#include <map>
#include <unordered_map>
#include <numeric>
#include <functional>
#define _overload3(_1,_2,_3,name,...) name
#define _rep(i,n) repi(i,0,n)
#define repi(i,a,b) for(ll i=ll(a);i<ll(b);++i)
#define rep(...) _overload3(__VA_ARGS__,repi,_rep,)(__VA_ARGS__)
#define rrep(i,a) for(ll i=ll(a-1);i>=0;--i)
#define all(x) (x).begin(),(x).end()
#define PRINT(V) cout << V << "\n"
#define SORT(V) sort((V).begin(),(V).end())
#define RSORT(V) sort((V).rbegin(), (V).rend())
using namespace std;
using ll = long long;
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 (b<a) { a=b; return 1; } return 0; }
inline void Yes(bool condition){ if(condition) PRINT("Yes"); else PRINT("No"); }
template<class itr> void cins(itr first,itr last){
    for (auto i = first;i != last;i++){
        cin >> (*i);
    }
}
template<class itr> void array_output(itr start,itr goal){
    string ans = "",k = " ";
    for (auto i = start;i != goal;i++) ans += to_string(*i)+k;
    if (!ans.empty()) ans.pop_back();
    PRINT(ans);
}
ll gcd(ll a, ll b) {
    return a ? gcd(b%a,a) : b;
}

const int INF = 1e9;
const ll MOD = 1000000007;
const ll MOD2 = 998244353;
const ll EPS = 1e-10;
int sgn(const double a){
    return (a < -EPS ? -1 : (a > EPS ? +1 : 0));
}
typedef pair<ll,ll> P;
typedef tuple<ll,ll,ll> tri;
typedef pair<double,double> point;
typedef complex<double> Point;
const ll MAX = 100005;
constexpr ll nx[4] = {-1,0,1,0};
constexpr ll ny[4] = {0,1,0,-1};
vector<vector<ll>> g(MAX);
vector<ll> a(MAX),b(MAX);
P dfs(ll v,ll par){
    ll d = a[v],nd = 0;
    for (ll u:g[v]){
        if (u == par) continue;
        ll s,t;
        tie(s,t) = dfs(u,v);
        d += max(s,t);
        nd += max(s,t+b[u]+b[v]);
    }
    return P(d,nd);
}
int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);
    ll n;
    cin >> n;
    rep(i,n) cin >> a[i];
    rep(i,n) cin >> b[i];
    rep(i,n-1){
        ll u,v;
        cin >> u >> v;
        u--;v--;
        g[u].push_back(v);
        g[v].push_back(u);
    }
    ll s,t;
    tie(s,t) = dfs(0,-1);
    PRINT(max(s,t));
}