#include <bits/stdc++.h>
using namespace std;
#define int long long
#define rep(i,n) for(int (i)=0;(i)<(n);(i)++)
#define rrep(i,n) for(int (i)=((n)-1);(i)>=0;(i)--)
#define itn int
#define miele(v) min_element(v.begin(), v.end())
#define maele(v) max_element(v.begin(), v.end())
#define SUM(v) accumulate(v.begin(), v.end(), 0LL)
#define lb(a, key) lower_bound(a.begin(),a.end(),key)
#define ub(a, key) upper_bound(a.begin(),a.end(),key)
#define COUNT(a, key) count(a.begin(), a.end(), key) 
#define BITCOUNT(x) __builtin_popcount(x)
#define pb push_back
#define all(x) (x).begin(),(x).end()
#define F first
#define S second
using P = pair <int,int>;
using WeightedGraph = vector<vector <P>>;
using UnWeightedGraph = vector<vector<int>>;
using Real = long double;
using Point = complex<Real>; //Point and Vector2d is the same!
using Vector2d = complex<Real>;
const long long INF = 1LL << 60;
const int MOD = 1000000007;
const double EPS = 1e-15;
const double PI=3.14159265358979323846;
template <typename T> 
int getIndexOfLowerBound(vector <T> &v, T x){
    return lower_bound(v.begin(),v.end(),x)-v.begin();
}
template <typename T> 
int getIndexOfUpperBound(vector <T> &v, T x){
    return upper_bound(v.begin(),v.end(),x)-v.begin();
}
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; }
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }
#define DUMPOUT cerr
#define repi(itr, ds) for (auto itr = ds.begin(); itr != ds.end(); itr++)
istream &operator>>(istream &is, Point &p) {
    Real a, b; is >> a >> b; p = Point(a, b); return is;
}
template <typename T, typename U>
istream &operator>>(istream &is, pair<T,U> &p_var) {
    is >> p_var.first >> p_var.second;
    return is;
}
template <typename T>
istream &operator>>(istream &is, vector<T> &vec) {
    for (T &x : vec) is >> x;
    return is;
}
template <typename T, typename U>
ostream &operator<<(ostream &os, pair<T, U> &pair_var) {
    DUMPOUT<<'{';
    os << pair_var.first;
    DUMPOUT<<',';
    os << " "<< pair_var.second;
    DUMPOUT<<'}';
    return os;
}
template <typename T>
ostream &operator<<(ostream &os, vector<T> &vec) {
    DUMPOUT<<'[';
    for (int i = 0; i < vec.size(); i++) 
    os << vec[i] << (i + 1 == vec.size() ? "" : " ");
    DUMPOUT<<']';
    return os;
}
template <typename T>
ostream &operator<<(ostream &os, vector<vector<T>> &df) {
  for (auto& vec : df) os<<vec;
  return os;
}
template <typename T, typename U>
ostream &operator<<(ostream &os, map<T, U> &map_var) {
    DUMPOUT << "{";
    repi(itr, map_var) {
        os << *itr;
        itr++;
        if (itr != map_var.end()) DUMPOUT << ", ";
        itr--;
    }
    DUMPOUT << "}";
    return os;
}
template <typename T>
ostream &operator<<(ostream &os, set<T> &set_var) {
    DUMPOUT << "{";
    repi(itr, set_var) {
        os << *itr;
        itr++;
        if (itr != set_var.end()) DUMPOUT << ", ";
        itr--;
    }
    DUMPOUT << "}";
    return os;
}
void print() {cout << endl;}
template <class Head, class... Tail>
void print(Head&& head, Tail&&... tail) {
  cout << head;
  if (sizeof...(tail) != 0) cout << " ";
  print(forward<Tail>(tail)...);
}
void dump_func() {DUMPOUT << '#'<<endl;}
template <typename Head, typename... Tail>
void dump_func(Head &&head, Tail &&... tail) {
    DUMPOUT << head;
    if (sizeof...(Tail) > 0) DUMPOUT << ", ";
    dump_func(std::move(tail)...);
}
#ifdef DEBUG_
#define DEB
#define dump(...)                                                              \
    DUMPOUT << "  " << string(#__VA_ARGS__) << ": "                            \
            << "[" << to_string(__LINE__) << ":" << __FUNCTION__ << "]"        \
            << endl                                                            \
            << "    ",                                                         \
        dump_func(__VA_ARGS__)
#else
#define DEB if (false)
#define dump(...)
#endif

vector <int> tax;
template <typename T>
struct doubling{
    int sz;
    vector <vector <T>> parents, maxEdge, minEdge;
    vector <int> dep;
    doubling(WeightedGraph &g){
        sz = g.size();
        parents.resize(21), maxEdge.resize(21), minEdge.resize(21), dep.resize(sz);
        rep(i, 21) parents[i].resize(sz), maxEdge[i].resize(sz), minEdge[i].resize(sz);
        queue <tuple <int,int,int,int>> q;
        q.push(make_tuple(0, 0, 0, 0)); //now, pre, cost depth
        while(!q.empty()){
            auto tmp = q.front(); q.pop();
            int now = get <0>(tmp), pre = get <1>(tmp), cost = get <2>(tmp), depth = get <3>(tmp);
            parents[0][now] = pre, maxEdge[0][now] = cost, minEdge[0][now] = cost, dep[now] = depth;
            for(auto ne: g[now]){
                if(ne.F != pre){
                    q.push(make_tuple(ne.F, now, ne.S, depth+1));
                }
            }
        }
        for(int i=1;i<21;i++){
            rep(j, sz){
                int ma = -INF, mi = INF;
                parents[i][j] = parents[i-1][j];
                maxEdge[i][j] = maxEdge[i-1][j];
                minEdge[i][j] = minEdge[i-1][j];
                int ne = parents[i][j];
                parents[i][j] = parents[i-1][ne];
                chmin(minEdge[i][j], minEdge[i-1][ne]);
                chmax(maxEdge[i][j], maxEdge[i-1][ne]);
            }
        }
    }
    int getAncestor(int a, int dist){
        int now = a;
        for(int i=19;i>=0;i--) if(dist&(1<<i)) now = parents[i][now];
        return now;
    }
    int lca(int a, int b){
        if(a==b) return a;
        if(dep[a] > dep[b]) swap(a, b);
        for(int i=19;i>=0;i--) if(((dep[b] - dep[a]) >> i) & 1) b = parents[i][b];
        if(a==b) return a;
        for(int i=19;i>=0;i--) 
        if(parents[i][a] != parents[i][b]) a = parents[i][a], b = parents[i][b];
        return parents[0][a];
    }
    int dist(int a, int b){
        int anc = lca(a, b);
        dump(a, b , anc);
        return dep[a] + dep[b] - 2*dep[anc];
    }
    int getMaxEdge(int a, int b){ //確実にバグがあります
        int res = 0;
        int anc = lca(a, b);
        int now1 = a, now2 = b;
        int dist1 = dep[a] - dep[anc], dist2 = dep[b] - dep[anc];
        for(int i=20;i>=0;i--){
            if(dist1&(1LL<<i)) {
                chmax(res, maxEdge[i][now1]);
                now1 = parents[i][now1];
            }
            if(dist2&(1LL<<i)) {
                chmax(res, maxEdge[i][now2]);
                now2 = parents[i][now2];
            }
        }
        return res;
    }
    int getMinEdge(int a, int b){ //確実にバグがあります
        int res = 0;
        int anc = lca(a, b);
        int now1 = a, now2 = b;
        int dist1 = dep[a] - dep[anc], dist2 = dep[b] - dep[anc];
        for(int i=20;i>=0;i--){
            if(dist1&(1LL<<i)) {
                chmin(res, minEdge[i][now1]);
                now1 = parents[i][now1];
            }
            if(dist2&(1LL<<i)) {
                chmin(res, minEdge[i][now2]);
                now2 = parents[i][now2];
            }
        }
        return res;
    }
};

struct EulerTour{
    vector <int> eulertour, l, r;
    EulerTour(UnWeightedGraph &g){
        dfs(g);
        l.resize(g.size(), 1145141919), r.resize(g.size());
        rep(i, eulertour.size()){
            if(l[eulertour[i]]==1145141919) l[eulertour[i]] = i;
            r[eulertour[i]] = i;
        }
    }
    void dfs(UnWeightedGraph &g, int now = 0, int mae = -1){
        //dump(now);
        eulertour.pb(now);
        for(auto e: g[now]){
            if(e != mae) {
                dfs(g, e, now);
                eulertour.pb(now);
            }
        }
    }
};
struct SegTree{
    int n;
    vector <int> node;
    SegTree(vector <int> v){
        int sz = v.size();
        n = 1;
        while(n<sz) n*=2;
        node.resize(2*n-1);
        for(int i=0; i<sz; i++) node[i+n-1] = v[i]; //一番下側
        for(int i=n-2;i>=0;i--) node[i] = node[2*i+1] + node[2*i+2];
    }
    void add(int number, int val){
        number += n-1;
        node[number] += val;
        while(number>0){
            number=(number-1)/2;
            node[number] = node[number*2+1] + node[number*2+2];
        }
    }
    int getsum(int a, int b, int k=0, int l = 0, int r = -1){
        if(r<0) r=n;
        if(r<=a||l>=b) return 0;
        if(a <= l&& r<=b) return node[k];
        int vl = getsum(a, b, 2*k+1, l, (l+r)/2);
        int vr = getsum(a, b, 2*k+2, (l+r)/2, r);
        return vl + vr;
    }
};

vector <int> parent;
void dfs(int now, int mae, UnWeightedGraph & g){
    parent[now] = mae;
    for(auto e: g[now]) if(mae != e) dfs(e, now, g);
}
WeightedGraph g;
UnWeightedGraph gg;
signed main(void) { cin.tie(0); ios::sync_with_stdio(false);
    int n; cin>>n;
    g.resize(n), gg.resize(n), parent.resize(n);
    vector <pair<int,int>> p(n-1);
    cin>>p;
    tax.resize(n);
    cin>>tax;
    map <P, int> ma;
    rep(i, n-1){
        int a = p[i].F, b = p[i].S;
        g[a].pb({b, tax[b]});
        g[b].pb({a, tax[a]});
        gg[a].pb(b);
        gg[b].pb(a);
    }

    dfs(0, -1, gg);

    rep(i, n-1){
        int a = p[i].F, b = p[i].S;
        if(parent[a] == b){
            ma[{a, b}] = -tax[a];
            ma[{b, a}] = tax[a];
        }else {
            ma[{a, b}] = tax[b];
            ma[{b, a}] = -tax[b];
        }
    }

    EulerTour et(gg);
    vector <int> etv = et.eulertour;

    vector <int> tmp(etv.size());
    rep(i, etv.size()){
        if(i == 0) continue;
        tmp[i] = ma[{etv[i-1], etv[i]}];
    }
    SegTree seg(tmp);
    
    int ans = 0;
    doubling <int> dou(g);
    int q; cin>>q;
    rep(i, q){
        int a, b, c; cin>>a>>b>>c;
        int anc = dou.lca(a, b);
        /*dump(a, b, anc);
        dump(seg.getsum( et.l[anc]+1, et.r[a]+1) + seg.getsum(et.l[anc]+1, et.r[b]+1));*/
        ans += (seg.getsum( et.l[anc]+1, et.r[a]+1) + seg.getsum(et.l[anc]+1, et.r[b]+1) + tax[anc])*c;
    }
    print(ans);
}