#include <bits/stdc++.h>
using namespace std;
const int N = 100005;
struct Go {
int u, v, w;
Go (int u, int v, int w) :
u(u), v(v), w(w) {}
};
int n, m, cnt;
int st[N], ed[N];
int h[N], p[20][N];
int f[2][N];
int it[4 * N];
int lazy[4 * N];
vector<int> G[N];
vector<Go> go[N];
void dfs(int u) {
st[u] = ++cnt;
for (auto v : G[u]) {
if (p[0][u] == v) continue;
p[0][v] = u, h[v] = h[u] + 1, dfs(v);
}
ed[u] = cnt;
}
void push(int i, int l, int r) {
if (!lazy[i]) return;
if (l == r) it[i] += lazy[i];
else lazy[i << 1] += lazy[i], lazy[i << 1 | 1] += lazy[i];
lazy[i] = 0;
}
void upd(int i, int l, int r, int u, int v, int x) {
push(i, l, r);
if (l > v || u > r) return;
if (u <= l && r <= v) {
lazy[i] = x, push(i, l, r); return;
}
int mid = (l + r) >> 1;
upd(i << 1, l, mid, u, v, x);
upd(i << 1 | 1, mid + 1, r, u, v, x);
}
int get(int i, int l, int r, int p) {
push(i, l, r);
if (l == r) return it[i];
int mid = (l + r) >> 1;
if (mid >= p) return get(i << 1, l, mid, p);
return get(i << 1 | 1, mid + 1, r, p);
}
void solve(int u) {
for (auto v : G[u]) {
if (p[0][u] == v) continue;
solve(v), f[0][u] += f[1][v];
}
f[1][u] = f[0][u];
for (auto i : go[u]) {
int cur = f[0][u] + i.w;
if (i.u != u) {
int x = i.u;
for (int i = 17; i >= 0; --i) {
if (h[p[i][x]] > h[u]) x = p[i][x];
}
cur += get(1, 1, n, st[i.u]) + f[0][i.u] - f[1][x];
}
if (i.v != u) {
int x = i.v;
for (int i = 17; i >= 0; --i) {
if (h[p[i][x]] > h[u]) x = p[i][x];
}
cur += get(1, 1, n, st[i.v]) + f[0][i.v] - f[1][x];
}
f[1][u] = max(f[1][u], cur);
}
for (auto v : G[u]) {
if (p[0][u] == v) continue;
upd(1, 1, n, st[v], ed[v], f[0][u] - f[1][v]);
}
}
int lca(int u, int v) {
if (h[u] > h[v]) swap(u, v);
for (int i = 17; i >= 0; --i) {
if (h[p[i][v]] >= h[u]) v = p[i][v];
}
for (int i = 17; i >= 0; --i) {
if (p[i][v] != p[i][u]) v = p[i][v], u = p[i][u];
}
return (u == v) ? u : p[0][u];
}
int main() {
ios::sync_with_stdio(false);
cin >> n;
for (int i = 0; i < (n - 1); ++i) {
int u, v; cin >> u >> v;
G[u].push_back(v), G[v].push_back(u);
}
p[0][1] = h[1] = 1, dfs(1);
for (int i = 1; i <= 17; ++i) {
for (int j = 1; j <= n; ++j) {
p[i][j] = p[i - 1][p[i - 1][j]];
}
}
cin >> m;
for (int i = 0; i < m; ++i) {
int u, v, w; cin >> u >> v >> w;
go[lca(u, v)].push_back(Go(u, v, w));
}
solve(1); cout << f[1][1] << '\n';
}
