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

typedef long long ll;
const int MAX_N = 100100;
const int MAX_LOG= 20;
ll n;

ll par[MAX_LOG][MAX_N];
ll depth[MAX_N];
ll cost[MAX_N];
vector<vector<ll> > G;
vector<ll> U;


void dfs(ll v,ll p, ll d, ll c){
	par[0][v]=p;
	depth[v]=d;
	cost[v]=c+U[v];
	for(auto nxt : G[v]){
		if(nxt !=p)
			dfs(nxt, v, d+1, c+U[v]);
	}
}

void setPar(){
	dfs(0,-1,0,0);
	for(ll i=0;i<MAX_LOG-1;i++){
		for(ll j=0;j<n;j++){
			if(par[i][j]== -1)
				par[i+1][j]= -1;
			else
				par[i+1][j]=par[i][par[i][j]];
		}
	}
}


ll lca(ll a,ll b){
	if(depth[a]>depth[b])
		swap(a,b);
	for(ll i=0;i<MAX_LOG;i++){
		if((depth[b]-depth[a]) >> i&1)
			b=par[i][b];
	}
	if(a==b) return a;
	
	for(ll i=MAX_LOG-1;i>=0;i--){
		if(par[i][a]!=par[i][b]){
			a=par[i][a];
			b=par[i][b];
		}
	}
	return par[0][a];
}

int main(){
	scanf("%lld",&n);
	G.resize(n);
	for(ll i=0;i<n-1;i++){
		ll a,b;
		scanf("%lld%lld", &a,&b);
		G[a].push_back(b);
		G[b].push_back(a);
	}
	
	U.resize(n);
	for(ll i=0;i<n;i++) scanf("%lld", &U[i]);
	
	setPar();
	
	ll Q;
	scanf("%lld",&Q);
	ll ans=0;
	for(ll i=0;i<Q;i++){
		ll a,b,m;
		scanf("%lld%lld%lld", &a,&b,&m);
		ll c=lca(a,b);
		ans+=(cost[a] + cost[b] - 2 * cost[c] + U[c]) * m;
	}
	
	printf("%lld\n", ans);
	return 0;
}