#include <bits/stdc++.h>
using namespace std;
using ll = long long;

class HLDecomposition {
	vector<vector<int>> g;
	vector<int> vid, head, heavy, parent, depth, inv;
	int dfs(int curr, int prev) {
		parent[curr] = prev;
		int sub = 1, max_sub = 0;
		for (int next : g[curr]) if (next != prev) {
			depth[next] = depth[curr] + 1;
			int sub_next = dfs(next, curr);
			sub += sub_next;
			if (max_sub < sub_next) max_sub = sub_next, heavy[curr] = next;
		}
		return sub;
	}
	void bfs() {
		int k = 0;
		queue<int> q({ 0 });
		while (!q.empty()) {
			int h = q.front(); q.pop();
			for (int i = h; i != -1; i = heavy[i]) {
				vid[i] = k++;
				inv[vid[i]] = i;
				head[i] = h;
				for (int j : g[i]) if (j != parent[i] && j != heavy[i]) q.push(j);
			}
		}
	}
public:
	HLDecomposition(int n)
		: g(n), vid(n, -1), head(n), heavy(n, -1), parent(n), depth(n), inv(n) {}

	void add(int u, int v) {
		g[u].push_back(v);
		g[v].push_back(u);
	}
	void build() {
		dfs(0, -1);
		bfs();
	}
	void for_each(int u, int v, function<void(int, int)> f) {
		if (vid[u] > vid[v]) swap(u, v);
		f(max(vid[head[v]], vid[u]), vid[v]);
		if (head[u] != head[v]) for_each(u, parent[head[v]], f);
	}
	void for_each_directed(int u, int v, function<void(int, int, int)> f) {
		if (vid[u] > vid[v]) {
			f(max(vid[head[u]], vid[v]), vid[u], 1);
			if (head[u] != head[v]) for_each_directed(parent[head[u]], v, f);
		}
		else {
			f(max(vid[head[v]], vid[u]), vid[v], 0);
			if (head[u] != head[v]) for_each_directed(u, parent[head[v]], f);
		}
	}
	void for_each_edge(int u, int v, function<void(int, int)> f) {
		if (vid[u] > vid[v]) swap(u, v);
		if (head[u] != head[v]) {
			f(vid[head[v]], vid[v]);
			for_each_edge(u, parent[head[v]], f);
		}
		else {
			if (u != v) f(vid[u] + 1, vid[v]);
		}
	}
	int ancestor(int u, int d) {
		while (true) {
			if (depth[head[u]] > depth[u] - d) {
				d -= depth[u] - depth[head[u]] + 1;
				if (head[u] == 0) return 0;
				u = parent[head[u]];
			}
			else {
				return inv[vid[u] - d];
			}
		}
	}
	int lca(int u, int v) {
		if (vid[u] > vid[v]) swap(u, v);
		if (head[u] == head[v]) return u;
		return lca(u, parent[head[v]]);
	}
	int distance(int u, int v) {
		return depth[u] + depth[v] - 2 * depth[lca(u, v)];
	}
};

template <typename T>
class SegmentTree {
	using func_t = function<T(T, T)>;
	const int n;
	const T id;
	func_t merge;
	vector<T> data;
	int size(int n) {
		int res;
		for (res = 1; res < n; res <<= 1);
		return res;
	}
	T sub(int l, int r, int node, int lb, int ub) {
		if (ub <= l || r <= lb) return id;
		if (l <= lb && ub <= r) return data[node];
		return merge(sub(l, r, node * 2, lb, (lb + ub) / 2), sub(l, r, node * 2 + 1, (lb + ub) / 2, ub));
	}
public:
	SegmentTree(int n_, T id_, func_t merge_) :
		n(size(n_)), id(id_), merge(merge_), data(size(n_) * 2, id_) {}
	void Init(const vector<T>& data_) {
		for (int i = 0; i < (int)data_.size(); i++)
			data[i + n] = data_[i];
		for (int i = n - 1; i >= 0; i--)
			data[i] = merge(data[i * 2], data[i * 2 + 1]);
	}
	void Update(int p, T val) {
		p += n;
		data[p] = val;
		while (p >>= 1) data[p] = merge(data[p * 2], data[p * 2 + 1]);
	}
	void Add(int p, T val) {
		p += n;
		data[p] += val;
		while (p >>= 1) data[p] = merge(data[p * 2], data[p * 2 + 1]);
	}
	T Find(int i) {
		return data[i + n];
	}
	T Find(int l, int r) {
		return sub(l, r + 1, 1, 0, n);
	}
};

int main()
{
	cin.sync_with_stdio(false);
	int N, M;
	cin >> N;
	HLDecomposition hl(N);
	for (int i = 0, A, B; i < N - 1; i++) {
		cin >> A >> B;
		hl.add(A, B);
	}
	hl.build();
	SegmentTree<ll> st(N, 0, [](ll l, ll r) { return l + r; });
	for (int i = 0, U; i < N; i++) {
		cin >> U;
		hl.for_each(i, i, [&](int l, int r) {
			st.Add(l, U);
		});
	}
	cin >> M;
	ll res = 0;
	for (int i = 0, A, B, C; i < M; i++) {
		cin >> A >> B >> C;
		ll tmp = 0;
		hl.for_each(A, B, [&](int l, int r) {
			tmp += st.Find(l, r);
		});
		res += tmp * C;
	}
	cout << res << endl;
	return 0;
}