#include <iostream>
#include <vector>
#define ll long long
#define pii pair<int, int>
#define ppi pair<pii, int>
#define fst first
#define snd second
using namespace std;
const int LG = 17;
struct BIT
{
int N; ll A[100001];
BIT() {}
BIT(int size) {N = size;}
void init(int size) {N = size;}
void update(int x, ll val)
{
for (; x <= N; x += x & (-x)) {A[x] += val;}
}
ll query(int x)
{
ll ret = 0;
for (; x; x -= x & (-x)) {ret += A[x];}
return ret;
}
};
int N, Q, h[100001], L[100001], R[100001], sps[100001][LG], idx = 1;
BIT D1, D2;
ll DP[100001];
vector<int> adj[100001];
vector<ppi> solve[100001];
void prep(int u, int p)
{
h[u] = (p == -1) ? 0 : (h[p] + 1); L[u] = R[u] = idx++;
sps[u][0] = p;
for (int i = 1; i < LG; i++)
{
if (sps[u][i - 1] != -1) sps[u][i] = sps[sps[u][i - 1]][i - 1];
else sps[u][i] = -1;
}
for (auto v : adj[u])
{
if (v != p)
{
prep(v, u);
R[u] = max(R[u], R[v]);
}
}
}
inline int getLCA(int u, int v)
{
if (h[u] > h[v]) {swap(u, v);}
for (int i = 0; h[v] - h[u]; i++)
{
if ((h[v] - h[u]) & (1 << i)) {v = sps[v][i];}
}
if (u == v) {return u;}
for (int i = LG - 1; i >= 0; i--)
{
if (sps[u][i] != sps[v][i]) {u = sps[u][i]; v = sps[v][i];}
}
return sps[u][0];
}
void DFS(int u, int p)
{
ll childSum = 0;
for (auto v : adj[u])
{
if (v != p) {DFS(v, u); childSum += DP[v];}
}
DP[u] = childSum;
for (auto v : solve[u])
{
ll v1 = D1.query(L[v.fst.fst]) + D1.query(L[v.fst.snd]);
ll v2 = D2.query(L[v.fst.fst]) + D2.query(L[v.fst.snd]);
DP[u] = max(DP[u], v1 - v2 + childSum + v.snd);
}
D1.update(L[u], childSum);
D1.update(R[u] + 1, -childSum);
D2.update(L[u], DP[u]);
D2.update(R[u] + 1, -DP[u]);
}
int main()
{
ios :: sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin >> N; D1.init(N); D2.init(N);
for (int i = 1; i < N; i++)
{
int u, v; cin >> u >> v;
adj[u - 1].push_back(v - 1);
adj[v - 1].push_back(u - 1);
}
prep(0, -1);
cin >> Q;
for (int i = 0; i < Q; i++)
{
int u, v, w; cin >> u >> v >> w; u--; v--;
solve[getLCA(u, v)].push_back({{u, v}, w});
}
DFS(0, -1);
cout << DP[0] << "\n";
return 0;
}
