#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
#define all(x) (x).begin(), (x).end()
#define size(x) (ll)x.size()
#define chkmax(x, y) x = max(x, y)
#define chkmin(x, y) x = min(x, y)
const int N = (1 << 17);
vector<int> g[N];
int sz[N], dth[N], pa[N];
void dfs(int v, int p) {
sz[v] = 1;
for(int to : g[v]) {
if (to == p) continue;
pa[to] = v;
dth[to] = dth[v] + 1;
dfs(to, v);
sz[v] += sz[to];
}
for(int i = 1; i < size(g[v]); i++) {
if (g[v][i] == p) continue;
if (g[v][0] == p || sz[g[v][0]] < sz[g[v][i]]) {
swap(g[v][0], g[v][i]);
}
}
}
int tt = 0;
int id[N], rid[N];
int head[N];
void dfs2(int v, int p, int h) {
head[v] = h;
id[v] = tt++;
rid[id[v]] = v;
for(int to : g[v]) {
if (to != p) {
if (to == g[v][0]) {
dfs2(to, v, h);
} else {
dfs2(to, v, to);
}
}
}
}
int n;
ll t[2 * N];
void upd(int v, int val) {
v += N - 1;
t[v] += val;
while (v > 0) {
v = (v - 1) >> 1;
t[v] = t[v * 2 + 1] + t[v * 2 + 2];
}
}
ll get(int v, int tl, int tr, int l, int r) {
if (l >= r) return 0;
if (tl == l && tr == r) return t[v];
int tm = (tl + tr) / 2;
return get(v * 2 + 1, tl, tm, l, min(r, tm)) + get(v * 2 + 2, tm, tr, max(l, tm), r);
}
ll get(int l, int r) {
return get(0, 0, N, l, r + 1);
}
ll sum(int p, int x) {
ll res = 0;
while (head[p] != head[x]) {
res += get(id[head[x]], id[x]);
x = pa[head[x]];
}
res += get(id[p], id[x]);
return res;
}
int lca(int a, int b) {
while (1) {
if (head[a] == head[b]) {
if (dth[a] < dth[b]) return a;
else return b;
}
if (dth[head[a]] < dth[head[b]]) swap(a, b);
a = pa[head[a]];
}
}
int a1[N], b1[N], c[N];
vector<int> e[N];
ll dp[N];
ll cur[N];
void Do(int v, int p) {
for(int to : g[v]) {
if (to != p) {
Do(to, v);
}
}
for(int to : g[v]) {
if (to != p) {
dp[v] += dp[to];
}
}
for(int x : e[v]) {
int a = a1[x], b = b1[x];
chkmax(dp[v], sum(v, a) + sum(v, b) - cur[v] + c[x]);
}
if (p != -1) {
cur[p] += dp[v];
upd(id[p], dp[v]);
upd(id[v], -dp[v]);
}
}
void run() {
cin >> n;
for(int i = 0; i < n - 1; i++) {
int a, b;
cin >> a >> b;
--a; --b;
g[a].push_back(b);
g[b].push_back(a);
}
dfs(0, -1);
dfs2(0, -1, 0);
int m;
cin >> m;
for(int i = 0; i < m; i++) {
cin >> a1[i] >> b1[i] >> c[i];
--a1[i]; --b1[i];
e[lca(a1[i], b1[i])].push_back(i);
}
Do(0, -1);
cout << dp[0];
}
int main() {
#ifdef LOCAL
freopen("input", "r", stdin);
freopen("output", "w", stdout);
#endif
ios::sync_with_stdio(false);
cin.tie(0);
cout << fixed << setprecision(10);
run();
}
