#include <bits/stdc++.h>
using namespace std;
const int N = 100100;
struct Path {
int from, to, cost;
Path(int from, int to, int cost) : from(from), to(to), cost(cost){}
};
int n;
vector<int> g[N];
int dep[N], par[17][N];
int tin[N], tout[N], tt;
int f[N], sf[N];
vector<Path> ps[N];
void dfs(int u, int p) {
tin[u] = ++tt;
for (int i = 1; i < 17; ++i) {
par[i][u] = par[i - 1][par[i - 1][u]];
}
for (int v : g[u]) if (v != p) {
dep[v] = dep[u] + 1;
par[0][v] = u;
dfs(v, u);
}
tout[u] = tt;
}
int lca(int u, int v) {
if (dep[u] > dep[v]) swap(u, v);
for (int i = 16; i >= 0; --i) {
if (dep[par[i][v]] >= dep[u]) {
v = par[i][v];
}
}
if (u == v) return u;
for (int i = 16; i >= 0; --i) {
if (par[i][u] != par[i][v]) {
u = par[i][u];
v = par[i][v];
}
}
return par[0][u];
}
int t[N << 2];
void add(int v, int l, int r, int L, int R, int val) {
if (L <= l && r <= R) {
t[v] += val;
return;
}
int md = (l + r) >> 1;
if (L <= md) add(v << 1, l, md, L, R, val);
if (md < R) add(v << 1 | 1, md + 1, r, L, R, val);
}
int get(int v, int l, int r, int p) {
if (l == r) {
return t[v];
}
int md = (l + r) >> 1;
int ans = t[v];
if (p <= md) ans += get(v << 1, l, md, p);
else ans += get(v << 1 | 1, md + 1, r, p);
return ans;
}
void solve(int u) {
for (int v : g[u]) if (v != par[0][u]) {
solve(v);
sf[u] += f[v];
}
for (int v : g[u]) if (v != par[0][u]) {
add(1, 1, n, tin[v], tout[v], sf[u] - f[v]);
}
f[u] = sf[u];
for (auto p : ps[u]) {
int from = p.from, to = p.to, cost = p.cost;
int val = sf[from] + sf[to] - sf[u] + cost;
val += get(1, 1, n, tin[from]);
val += get(1, 1, n, tin[to]);
f[u] = max(f[u], val);
}
}
int main() {
ios_base::sync_with_stdio(false);
cin >> n;
for (int i = 1; i < n; ++i) {
int u, v;
cin >> u >> v;
g[u].emplace_back(v);
g[v].emplace_back(u);
}
par[0][1] = 1;
dfs(1, 1);
int m;
cin >> m;
for (int i = 1; i <= m; ++i) {
int u, v, w;
cin >> u >> v >> w;
int a = lca(u, v);
ps[a].emplace_back(u, v, w);
}
solve(1);
cout << f[1] << '\n';
}
