#include <bits/stdc++.h>
using namespace std;
const int LOG = 19;
const int DIM = 200005;
int bit[DIM], anc[DIM][LOG], dp[DIM], aux[DIM], lev[DIM], fst[DIM], lst[DIM];
vector<tuple<int, int, int>> lis[DIM]; vector<int> edg[DIM];
void update(int p, int x) {
for (; p < DIM; p += (p & -p)) {
bit[p] += x; } }
int query(int p, int x = 0) {
for (; p > 0; p -= (p & -p)) {
x += bit[p]; }
return x; }
int lca(int x, int y) {
if (lev[x] > lev[y]) {
swap(x, y); }
for (int i = LOG - 1; i >= 0; --i) {
if (lev[y] - (1 << i) >= lev[x]) {
y = anc[y][i]; } }
for (int i = LOG - 1; i >= 0; --i) {
if (anc[x][i] != anc[y][i]) {
x = anc[x][i]; y = anc[y][i]; } }
return (x == y ? x : anc[x][0]); }
void dfs1(int x, int f) {
static int nr = 0;
fst[x] = ++nr; lev[x] = lev[f] + 1; anc[x][0] = f;
for (int i = 1; i < LOG; ++i) {
anc[x][i] = anc[anc[x][i - 1]][i - 1]; }
for (int y : edg[x]) {
if (y != f) {
dfs1(y, x); } }
lst[x] = ++nr; }
void dfs2(int x, int f) {
for (int y : edg[x]) {
if (y != f) {
dfs2(y, x); aux[x] += dp[y]; } }
dp[x] = aux[x];
for (auto &tp : lis[x]) {
int l, r, c; tie(l, r, c) = tp;
dp[x] = max(dp[x], query(fst[l]) + query(fst[r]) + aux[x] + c); }
update(fst[x], aux[x] - dp[x]); update(lst[x], dp[x] - aux[x]); }
int main(void) {
#ifdef HOME
freopen("election.in", "r", stdin);
freopen("election.out", "w", stdout);
#endif
int n; cin >> n;
for (int i = 1; i < n; ++i) {
int x, y; cin >> x >> y;
edg[x].push_back(y); edg[y].push_back(x); }
dfs1(1, 0); int m; cin >> m;
while (m--) {
int x, y, c; cin >> x >> y >> c;
lis[lca(x, y)].emplace_back(x, y, c); }
dfs2(1, 0); cout << dp[1] << "\n";
return 0; }
