#include<bits/stdc++.h>
using namespace std;
const int MAXN = 1.1e5;
int N, M;
vector<int> adj[MAXN];
int par[MAXN][20];
int depth[MAXN];
void dfs_par(int cur, int prv) {
if (prv) {
adj[cur].erase(find(adj[cur].begin(), adj[cur].end(), prv));
}
par[cur][0] = prv;
for (int i = 0; par[cur][i]; i++) {
par[cur][i+1] = par[par[cur][i]][i];
}
for (int nxt : adj[cur]) {
depth[nxt] = depth[cur] + 1;
dfs_par(nxt, cur);
}
}
int lca(int a, int b) {
if (depth[a] < depth[b]) swap(a, b);
int d = depth[a] - depth[b];
for (int i = 0; (1 << i) <= d; i++) {
if (d & (1 << i)) {
a = par[a][i];
}
}
assert(depth[a] == depth[b]);
if (a == b) return a;
int i = 0;
while (par[a][i]) i++;
while (i--) {
if (par[a][i] != par[b][i]) {
a = par[a][i];
b = par[b][i];
}
}
assert(par[a][0] == par[b][0]);
assert(a != b);
return par[a][0];
}
struct bit {
int a[MAXN];
bit() {
memset(a, 0, sizeof(a));
}
void update(int i, int v) {
for (i++; i <= N; i += (i & -i)) {
a[i] += v;
}
}
void update(int l, int r, int v) { // half open
update(l, +v);
update(r, -v);
}
int query(int i) { // value at i-th position
int ans = 0;
for (i++; i; i -= (i & -i)) {
ans += a[i];
}
return ans;
}
} bestsum, chsum;
vector<array<int, 3>> paths[MAXN];
int st[MAXN];
int en[MAXN];
int curind = 0;
int dfs(int cur) {
st[cur] = curind++;
int ch = 0;
for (int nxt : adj[cur]) {
ch += dfs(nxt);
}
en[cur] = curind;
int best = ch;
for (auto it : paths[cur]) {
int val = ch + it[2];
if (it[0] != cur) {
val -= bestsum.query(st[it[0]]);
val += chsum.query(st[it[0]]);
}
assert(it[1] != cur);
val -= bestsum.query(st[it[1]]);
val += chsum.query(st[it[1]]);
best = max(best, val);
}
bestsum.update(st[cur], en[cur], best);
chsum.update(st[cur], en[cur], ch);
return best;
}
int main() {
ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
cin >> N;
for (int i = 0; i < N-1; i++) {
int a, b; cin >> a >> b;
adj[a].push_back(b);
adj[b].push_back(a);
}
dfs_par(1, 0);
cin >> M;
for (int i = 0; i < M; i++) {
int a, b, c; cin >> a >> b >> c;
if (depth[a] > depth[b]) swap(a, b);
paths[lca(a, b)].push_back({a, b, c});
}
cout << dfs(1) << '\n';
return 0;
}
