#include <bits/stdc++.h>
using namespace std;
vector<int> in, out, dep, dp, dp2;
vector<vector<int>> g, up;
vector<vector<tuple<int, int, int>>> qr;
int t, lg;
struct fenwick {
vector<int> fenw;
int n;
void init(int n_) {
fenw.resize(n = n_);
}
void upd(int u, int x) {
for (; u < n; u |= u + 1) fenw[u] += x;
}
int qry(int u) {
int s = 0;
for (; u >= 0; u = (u & (u + 1)) - 1) s += fenw[u];
return s;
}
int qry(int l, int r) {
return qry(r) - qry(l - 1);
}
} fen;
void dfs(int u) {
in[u] = t++;
for (int i = 1; i < lg; i++) up[i][u] = up[i - 1][up[i - 1][u]];
for (int v : g[u])
if (v ^ up[0][u])
dep[v] = dep[u] + 1, up[0][v] = u, dfs(v);
out[u] = t++;
}
void calc_dp(int u, int p) {
for (int v : g[u])
if (v ^ p) {
calc_dp(v, u);
dp2[u] += dp[v];
}
dp[u] = dp2[u];
for (auto [x, y, w] : qr[u]) {
int cost = dp2[u] - fen.qry(in[u], in[x]) - fen.qry(in[u], in[y]);
dp[u] = max(dp[u], cost + w);
}
fen.upd(in[u], dp[u] - dp2[u]);
fen.upd(out[u], dp2[u] - dp[u]);
}
int lca(int u, int v) {
if (dep[u] < dep[v]) swap(u, v);
int k = dep[u] - dep[v];
for (int i = 0; i < lg; i++)
if (k >> i & 1)
u = up[i][u];
if (u == v) return u;
for (int i = lg - 1; i >= 0; i--)
if (up[i][u] ^ up[i][v])
u = up[i][u], v = up[i][v];
return up[0][u];
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
int n;
cin >> n;
while ((1 << lg) <= n) ++lg;
g.resize(n), up = vector<vector<int>> (lg, vector<int> (n)), dp.resize(n), dp2.resize(n), dep.resize(n), qr.resize(n), in.resize(n), out.resize(n);
for (int i = 0; i < n - 1; i++) {
int u, v;
cin >> u >> v;
--u, --v;
g[u].push_back(v);
g[v].push_back(u);
}
dfs(0);
fen.init(t);
int q;
cin >> q;
while (q--) {
int u, v, w;
cin >> u >> v >> w;
--u, --v;
qr[lca(u, v)].push_back({u, v, w});
}
calc_dp(0, 0);
cout << dp[0] << '\n';
}
