/*
Author: Nguyen Chi Thanh - High School for the Gifted - VNU.HCM (i2528)
*/
#include <bits/stdc++.h>
using namespace std;
#define int long long
#define ull unsigned long long
#define ld long double
#define pii pair<int, int>
#define fi first
#define se second
#define __builtin_popcount __builtin_popcountll
#define all(x) (x).begin(), (x).end()
#define BIT(x, i) (((x) >> (i)) & 1)
#define MASK(x) ((1ll << (x)))
#define debug(a, l, r) for (int _i = (l); _i <= (r); ++_i) cout << (a)[_i] << ' '; cout << '\n';
struct Query {
int u, v, c;
};
const int MAXN = 1e5 + 5;
const int INF = 1e18 + 5;
const int LG = 17;
int n, m;
vector<int> adj[MAXN];
vector<Query> queries[MAXN];
// LCA/Euler Tour Implementation
int depth[MAXN], up[LG + 1][MAXN];
int st[MAXN], en[MAXN], timer = 0;
void dfsLCA(int u, int par = 0) {
up[0][u] = par;
st[u] = ++timer;
for (int j = 1; j <= LG; ++j)
up[j][u] = up[j - 1][up[j - 1][u]];
for (int v : adj[u]) {
if (v == par) continue;
depth[v] = depth[u] + 1;
dfsLCA(v, u);
}
en[u] = timer;
}
int lift(int u, int k) {
for (int j = 0; j <= LG; ++j)
if (BIT(k, j)) u = up[j][u];
return u;
}
int lca(int u, int v) {
if (depth[u] > depth[v]) swap(u, v);
int diff = depth[v] - depth[u];
v = lift(v, diff);
if (u == v) return u;
for (int j = LG; j >= 0; --j) {
if (up[j][u] != up[j][v]) {
u = up[j][u];
v = up[j][v];
}
}
return up[0][u];
}
// End of LCA/Euler Tour Implementation
// Data Structures
struct FenwickTree {
int n;
vector<int> fen;
FenwickTree() {}
FenwickTree(int _n) : n(_n), fen(n + 5, 0) {}
void update(int idx, int v) {
for (int i = idx; i <= n; i += i & -i)
fen[i] += v;
}
int get(int idx) {
int sum = 0;
for (int i = idx; i; i -= i & -i)
sum += fen[i];
return sum;
}
void updateRange(int l, int r, int v) {
update(l, v);
update(r + 1, -v);
}
};
// End of Data Structures
void init() {
cin >> n;
for (int i = 1; i < n; ++i) {
int u, v; cin >> u >> v;
adj[u].push_back(v);
adj[v].push_back(u);
}
dfsLCA(1);
cin >> m;
for (int i = 1; i <= m; ++i) {
int u, v, c; cin >> u >> v >> c;
int at = lca(u, v);
queries[at].push_back({u, v, c});
}
}
// Main algorithm (DP on Tree)
int dp[2][MAXN];
/*
dp[used][u]: maximum value when consider subtree rooted at u
used = 0: not choose u
used = 1: choose u
*/
FenwickTree fen;
void dfs(int u, int par = 0) {
// Computing dp[0][u]
dp[0][u] = 0;
for (int v : adj[u]) {
if (v == par) continue;
dfs(v, u);
dp[0][u] += max(dp[0][v], dp[1][v]);
}
// Computing dp[1][u]
for (auto &qry : queries[u]) {
int a = qry.u, b = qry.v;
int val = dp[0][u];
if (a != u) {
// int p = lift(a, depth[a] - depth[u] - 1);
val += fen.get(st[a]);
// val -= max(dp[0][p], dp[1][p]);
}
if (b != u) {
// int p = lift(b, depth[b] - depth[u] - 1);
val += fen.get(st[b]);
// val -= max(dp[0][p], dp[1][p]);
}
dp[1][u] = max(dp[1][u], val + qry.c);
}
fen.updateRange(st[u], en[u], dp[0][u] - max(dp[0][u], dp[1][u]));
}
void solve() {
fen = FenwickTree(n);
for (int i = 1; i <= n; ++i)
dp[0][i] = dp[1][i] = -INF;
dfs(1);
cout << max(dp[0][1], dp[1][1]);
}
signed main() {
#ifdef NCTHANH
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif
ios_base::sync_with_stdio(0);
cin.tie(nullptr); cout.tie(nullptr);
init();
solve();
return 0;
}
