#include <iostream>
#include <iomanip>
#include <string>
#include <cmath>
#include <algorithm>
#include <vector>
#include <set>
#include <map>
#include <unordered_map>
#include <unordered_set>
#include <list>
#include <stack>
#include <queue>
#include <bitset>
#include <numeric>
#include <cassert>
#ifdef DEBUG
#include "./Lib/debug.hpp"
#else
#define dump(...)
template<class T>inline auto d_val(T a, T b) { return a; }
#endif

/* (=＾o＾=) */
#define int ll

/* macro */
#define FOR(i, b, e) for(ll i = (ll)(b); i < (ll)(e); ++i)
#define RFOR(i, b, e) for(ll i = (ll)(e-1); i >= (ll)(b); --i)
#define REP(i, n) FOR(i, 0, n)
#define RREP(i, n) RFOR(i, 0, n)
#define REPC(x,c) for(const auto& x:(c))
#define REPI2(it,b,e) for(auto it = (b); it != (e); ++it)
#define REPI(it,c) REPI2(it, (c).begin(), (c).end())
#define RREPI(it,c) REPI2(it, (c).rbegin(), (c).rend())
#define REPI_ERACE2(it, b, e) for(auto it = (b); it != (e);)
#define REPI_ERACE(it, c) REPI_ERACE2(it, (c).begin(), (c).end())
#define ALL(x) (x).begin(),(x).end()
#define cauto const auto&
/* macro func */
#define SORT(x) do{sort(ALL(x));}while(false)
#define RSORT(x) do{sort((x).rbegin(),(x).rend());}while(false)
#define UNIQUE(v) do{v.erase( unique(v.begin(), v.end()), v.end() );}while(false)
#define MAX(x,y) do{x = std::max(x,y);}while(false)
#define MIN(x,y) do{x = std::min(x,y);}while(false)
#define BR do{cout<<"\n";}while(false)

/* type define */
using ll = long long;
using PAIR = std::pair<ll, ll>;
using VS = std::vector<std::string>;
using VL = std::vector<long long>;
using VVL = std::vector<VL>;
using VVVL = std::vector<VVL>;
using VD = std::vector<double>;
template<class T>
using V = std::vector<T>;

/* using std */
using std::cout;
constexpr char endl = '\n';
using std::cin;
using std::sort;
using std::pair;
using std::string;
using std::stack;
using std::queue;
using std::vector;
using std::list;
using std::map;
using std::unordered_map;
using std::multimap;
using std::unordered_multimap;
using std::set;
using std::unordered_set;
using std::unordered_multiset;
using std::multiset;
using std::bitset;
using std::priority_queue;

/* constant value */
constexpr ll MOD = 1000000007;
//constexpr ll MOD = 998244353;

/* Initial processing  */
struct Preprocessing { Preprocessing() { std::cin.tie(0); std::ios::sync_with_stdio(0); }; }_Preprocessing;

/* Remove the source of the bug */
signed pow(signed, signed) { assert(false); return -1; }

/* define hash */
namespace std { template <>	class hash<std::pair<ll, ll>> { public:	size_t operator()(const std::pair<ll, ll>& x) const { return hash<ll>()(1000000000 * x.first + x.second); } }; }

/* input */
template<class T> std::istream& operator >> (std::istream& is, vector<T>& vec) { for (T& x : vec) is >> x; return is; }

//=============================================================================================
/**
 *	セグメント木を構成する
 *	2methodの変更により調整
 */
template<class T>
class SegmentTree {
private:
	const T initialValue = 0;
	const T ignoreValue = 0;

	const ll m_size;
	vector<T> m_node;

	ll calcSize(ll n) {
		ll size = 1;
		while (size < n) {
			size *= 2;
		}
		return size;
	}

	/**
	 * 値の更新(更新:=, 加算:+=, etc...)
	 */
	void update(ll k, T x) {
		m_node[k] = x;
	}

	/**
	* 値の併合
	*/
	T merge(T xl, T xr) {
		return xl + xr;
	}
public:
	SegmentTree(ll n) :
		m_size(calcSize(n)),
		m_node(m_size * 2 - 1, initialValue) {}

	void add(ll itr, T val) {
		ll i = itr + m_size - 1;
		update(i, val);

		while (i > 0) {
			i = (i - 1) / 2;
			m_node[i] = merge(m_node[i * 2 + 1], m_node[i * 2 + 2]);
		}
		/**
		cout << "-- tree -- " << endl;
		REP(i, 2 * m_size - 1) {
			cout << m_node[i] << endl;
		}
		/*//**/
	}

	T query(ll a, ll b) { return query(a, b + 1, 0, 0, m_size); }
	T query(ll a, ll b, ll k, ll l, ll r) {
		if (r <= a || b <= l) { return ignoreValue; }
		if (a <= l && r <= b) { return m_node[k]; }
		return merge(
			query(a, b, 2 * k + 1, l, (l + r) / 2),
			query(a, b, 2 * k + 2, (l + r) / 2, r)
		);
	}
};


class HLDecomposition {
	std::unordered_multimap<int, int> m_graph;
	std::unordered_map<int, int> m_graphRev;

	const int m_root;
	std::vector<int> m_nodeList;
	std::vector<int> m_nodeListPos;
	std::vector<int> m_nodeCostList;
	std::vector<std::pair<int, int>> m_nodeRange;

	SegmentTree<int> m_tree;

	static auto reverse(const std::unordered_multimap<int, int>& graph) {
		std::unordered_map<int, int> graphRev;
		for (const auto& p : graph) { graphRev.emplace(p.second, p.first); }
		return graphRev;
	}

	static auto getRoot(int size, const unordered_multimap<int, int>& graph) {
		std::vector<bool> children(size, false);
		for (const auto& p : graph) { children[p.second] = true; }
		for (int i = 0; i < size; ++i)if (!children[i]) { return i; }
	}

	static auto getTreeSize(int size, const unordered_multimap<int, int>& graph, int root) {
		auto treeSize = std::vector<int>(size, 1);
		auto calcTreeSize = [&](auto f, auto from) {
			auto range = graph.equal_range(from);
			if (range.first == range.second) {

				return;
			}
			for (auto itr = range.first; itr != range.second; ++itr) {
				auto to = itr->second;
				f(f, to);
				treeSize[from] += treeSize[to];
			}
		};
		calcTreeSize(calcTreeSize, root);
		return treeSize;
	}

	auto decomposition(const unordered_multimap<int, int>& graph, const std::vector<int>& nodeCost, const std::vector<int>& tSize, int now, int&& nodeFrom) {
		if (nodeFrom == -1) { nodeFrom = now; }
		m_nodeList.emplace_back(now);
		m_nodeCostList.emplace_back(nodeCost[now]);
		m_nodeListPos[now] = m_nodeList.size() - 1;
		m_nodeRange.emplace_back(m_nodeListPos[nodeFrom], -1);
		auto range = graph.equal_range(now);
		if (range.first == range.second) {
			for (int f = m_nodeListPos[nodeFrom]; f <= m_nodeListPos[now]; ++f) {
				m_nodeRange[f].second = m_nodeListPos[now];
			}
			nodeFrom = -1;
			return;
		}
		auto large = -1;
		auto sMax = -1;
		for (auto itr = range.first; itr != range.second; ++itr) {
			auto to = itr->second;
			if (tSize[to] > sMax) { sMax = tSize[to]; large = to; }
		}
		decomposition(graph, nodeCost, tSize, large, std::forward<int>(nodeFrom));
		for (auto itr = range.first; itr != range.second; ++itr) {
			auto to = itr->second;
			if (to == large) { continue; }
			decomposition(graph, nodeCost, tSize, to, std::forward<int>(nodeFrom));
		}
	}

	auto construct(int size, const unordered_multimap<int, int>& graph, const std::vector<int>& nodeCost) {
		m_nodeList.reserve(size);
		m_nodeCostList.reserve(size);
		m_nodeRange.reserve(size);
		decomposition(graph, nodeCost, getTreeSize(size, graph, m_root), m_root, -1);
	}

public:
	HLDecomposition(int size, const unordered_multimap<ll, ll>& graph, const std::vector<int>& nodeCost) :
		m_graph(graph), m_graphRev(reverse(m_graph)),
		m_root(getRoot(size, graph)), m_nodeListPos(size),
		m_tree(size) {
		construct(size, graph, nodeCost);
		for (int i = 0; i < size; ++i) { m_tree.add(i, m_nodeCostList[i]); }
	}
	HLDecomposition(int size, const unordered_multimap<int, int>& graph) :
		m_graph(graph), m_graphRev(reverse(m_graph)),
		m_root(getRoot(size, graph)), m_nodeListPos(size),
		m_tree(size) {
		construct(size, graph, std::vector<int>(size));
		for (int i = 0; i < size; ++i) { m_tree.add(i, m_nodeCostList[i]); }
	}

	void debugOutput() const {
		dump(m_nodeList, m_nodeCostList, m_nodeRange);
	}

	/**
	 * 最小共通祖先，LCA(Lowest Common Ancestor)を得る
	 */
	auto LCA(int a, int b) {
		while (a != b) {
			auto posa = m_nodeListPos[a];
			auto posb = m_nodeListPos[b];
			if (posa > posb) { std::swap(posa, posb); a = m_nodeList[posa]; }
			if (m_nodeRange[posb].first <= posa && posa <= m_nodeRange[posb].second) {
				b = a; break;
			}
			b = m_graphRev[m_nodeList[m_nodeRange[posb].first]];
		}
		return a;
	}

	/**
	 * セグ木を更新
	 *//**/
	auto add(int itr, int x) {
		m_tree.add(itr, x);
	}/*/**/

	/**
	* (遅延)セグ木から値を取得
	*/
	auto query(int a, int b) {
		ll val = 0;//TODO:
		bool flg = false;
		while (a != b) {
			auto posa = m_nodeListPos[a];
			auto posb = m_nodeListPos[b];
			if (posa > posb) { std::swap(posa, posb); a = m_nodeList[posa]; }
			if (m_nodeRange[posb].first <= posa && posa <= m_nodeRange[posb].second) {
				val += m_tree.query(posa, posb);
				flg = true;
				b = a; break;
			}
			auto t = m_nodeRange[posb].first;
			val += m_tree.query(m_nodeRange[posb].first, posb);
			b = m_graphRev[m_nodeList[m_nodeRange[posb].first]];
		}
		if (!flg) { val += m_tree.query(a, a); }
		return val;
	}
};


signed main() {
	ll n;
	cin >> n;
	unordered_multimap<ll, ll> graph_;
	REP(_, n - 1) {
		ll a, b;
		cin >> a >> b;
		graph_.emplace(a, b);
		graph_.emplace(b, a);
	}

	unordered_multimap<ll, ll> graph;
	{
		V<bool> use(n);
		queue<ll> q;
		q.emplace(0);
		use[0] = true;
		while (!q.empty()) {
			ll from = q.front();
			q.pop();
			auto range = graph_.equal_range(from);
			REPI2(itr, range.first, range.second) {
				ll to = itr->second;
				if (!use[to]) {
					q.emplace(to);
					use[to] = true;
					graph.emplace(from, to);
				}
			}
		}
	}
	VL cost(n);
	cin >> cost;
	auto tree = HLDecomposition(n, graph, cost);

	ll q;
	cin >> q;
	ll ans = 0;
	REP(_, q) {
		ll a, b, c;
		cin >> a >> b >> c;
		ans += tree.query(a, b) * c;
	}
	cout << ans << endl;
}