#include "bits/stdc++.h"
using namespace std;
using     ll=long long;
using    vll=vector<   ll>;
using   vvll=vector<  vll>;
using  vvvll=vector< vvll>;
using vvvvll=vector<vvvll>;
constexpr ll INF = 1LL << 60;
struct Fast{ //cin,cout高速化のおまじない＋桁数指定
	Fast(){ cin.tie(0); ios::sync_with_stdio(false); cout << fixed << setprecision(std::numeric_limits<double>::max_digits10); }
} fast;
#define rep(i, S, E)  for (ll i = (S); i <= (E); i++)
#define dep(i, E, S)  for (ll i = (E); i >= (S); i--)
#define each(e, v) for (auto&& e : v)
#define ALL(v) (v).begin(), (v).end()
#define RALL(v) (v).rbegin(), (v).rend()
template<class T> inline bool chmax(T &a, T b) { if (a < b) { a = b; return true; }return false; }
template<class T> inline bool chmin(T &a, T b) { if (a > b) { a = b; return true; }return false; }
template<class T> inline T MaxE(vector<T>&v,ll S,ll E){ T m=v[S]; rep(i,S,E)chmax(m,v[i]); return m; }
template<class T> inline T MinE(vector<T>&v,ll S,ll E){ T m=v[S]; rep(i,S,E)chmin(m,v[i]); return m; }
template<class T> inline T MaxE(vector<T> &v) { return MaxE(v,0,(ll)v.size()-1); }
template<class T> inline T MinE(vector<T> &v) { return MinE(v,0,(ll)v.size()-1); }
template<class T> inline T Sum(vector<T> &v,ll S,ll E){ T s=T(); rep(i,S,E)s+=v[i]; return s; }
template<class T> inline T Sum(vector<T> &v) { return Sum(v,0,v.size()-1); }
template<class T> inline ll sz(T &v){ return (ll)v.size(); }
template<class T> inline T POW(T a, ll n){ T r=1; for (; n>0; n>>=1, a*=a){ if (n&1)r*=a; } return r; }
inline ll POW(int a, ll n){ return POW((ll)a, n); }
inline ll CEIL(ll a, ll b){ return (a+b-1)/b; }


#if defined(_DEBUG)
ll dumpW = 5;
template<class T> void dump(vector<T> &v){
	rep(i,0,sz(v)-1) { cerr << ((i==0)?"[":" ") << setw(dumpW) << v[i]; }  cerr << "]";
}
void dump(vll &v){
	rep(i,0,sz(v)-1) {
		cerr << ((i==0)?"[":" ") << setw(dumpW);
		if (v[i] == INF) cerr << "INF";
		else if (v[i] == -INF) cerr << "-INF";
		else                   cerr << v[i];
	}  cerr << "]";
}
template<class T> void dump(vector<vector<T>> &v){
	ll N=(ll)v.size();  string d[2][2]={{" ", "["},  {"\n", "]\n"}};
	rep(i,0,N-1) { cerr << d[0][i==0];  dump(v[i]);  cerr << d[1][i==N-1]; }
}
template<class T> void dump(vector<vector<vector<T>>> &v){
	ll N=(ll)v.size();  string d[2]={"  <", "[ <"};
	rep(i,0,N-1) { cerr << d[i==0] << i << ">\n"; dump(v[i]); }  cerr << "]\n";
}
template<class T> void dump(vector<vector<vector<vector<T>>>> &v){
	ll N=(ll)v.size();  string d[2]={"  ---<", "[ ---<"};
	rep(i,0,N-1) { cerr << d[i==0] << i << ">---\n"; dump(v[i]); }  cerr << "]\n";
}
template<class T> void dump(vector<vector<vector<vector<vector<T>>>>> &v){
	ll N=(ll)v.size();  string d[2]={"  ======<", "[ ======<"};
	rep(i,0,N-1) { cerr << d[i==0] << i << ">======\n"; dump(v[i]); }  cerr << "]\n";
}
template<class T,class S> void dump(map<T,S> &m){
	for (auto e: m) cout << e.first << " : " << e.second << '\n';
}
#else
template<class T> void dump(T &v){}
#endif

vvll cinGraph(ll nodeNum,ll edgeNum,bool isDirected){//無向false、有向true
	vvll to(nodeNum);
	rep(i,0,edgeNum-1){
		ll v,u; cin >> v >> u;
		v--; u--;
		to[v].push_back(u);
		if (!isDirected) to[u].push_back(v);
	}
	return move(to);
}

vvll to;
vll a,b;
vvll dp;

void dfs(ll v,ll p){

	each(u,to[v]){
		if (u==p)continue;
		dfs(u,v);
	}

	dp[v][0]=a[v];
	dp[v][1]=0;

	each(u,to[v]){
		if (u==p)continue;
		dp[v][0]+=max(dp[u][0],dp[u][1]);
		dp[v][1]+=max(dp[u][0],dp[u][1]+b[u]+b[v]);
	}
}


void solve()
{
	ll n;  cin >> n;
	a.resize(n);  rep(i,0,n-1){ ll a_; cin>>a_; a[i]=a_; }
	b.resize(n);  rep(i,0,n-1){ ll b_; cin>>b_; b[i]=b_; }
	to = cinGraph(n,n-1,false);

	dp.resize(n,vll(2));
	
	dfs(0,-1);

	ll ans=max(dp[0][0],dp[0][1]);
	cout << ans << '\n';

}


int main(){
#if 1
	solve();
#else
	ll t;  cin >> t;
	rep(i, 0, t-1){
		solve();
	}
#endif
	return 0;
}