#include <bits/stdc++.h>
using namespace std;
using pii = pair<int, int>;
#define ff first
#define ss second
const int SIZE = 1 << 17;
struct ST {
int V[2 * SIZE];
void update(int s, int e, int v) {
for (s += SIZE, e += SIZE; s <= e; s >>= 1, e >>= 1) {
if ( s & 1) V[s++] += v;
if (~e & 1) V[e--] += v;
}
}
int query(int x) {
int ret = 0;
for (x += SIZE; x; x >>= 1) ret += V[x];
return ret;
}
} seg;
int dep[100005], par[17][100005], dfn[100005], efn[100005], dfnn, A[100005], B[100005], X[100005], Y[100005];
vector<pair<int, pii> > path[100005];
vector<int> edge[100005];
void dfs0(int x, int p) {
dep[x] = dep[p] + 1;
dfn[x] = ++dfnn;
par[0][x] = p;
for (int i = 1; i < 17; ++i) par[i][x] = par[i-1][par[i-1][x]];
for (auto i: edge[x]) {
if (i != p) dfs0(i, x);
}
efn[x] = dfnn;
}
int lca(int x, int y) {
if (dep[x] < dep[y]) swap(x, y);
for (int i = 0; i < 17; ++i)
if ((dep[x] - dep[y] >> i) & 1) x = par[i][x];
if (x == y) return x;
for (int i = 16; i >= 0; --i)
if (par[i][x] != par[i][y]) x = par[i][x], y = par[i][y];
return par[0][x];
}
void dfs(int x, int p) {
for (auto i: edge[x]) {
if (i == p) continue;
dfs(i, x);
B[x] += A[i];
}
A[x] = B[x];
for (auto i: edge[x]) {
if (i == p) continue;
seg.update(dfn[i], efn[i], B[x] - A[i]);
}
for (auto i: path[x]) {
A[x] = max(A[x], i.ff + B[i.ss.ff] + seg.query(dfn[i.ss.ff]) + B[i.ss.ss] + seg.query(dfn[i.ss.ss]) - B[x]);
}
}
int main() {
ios_base::sync_with_stdio(0), cin.tie(0);
int N, M; cin >> N;
for (int i = 1; i < N; ++i) {
cin >> X[i] >> Y[i];
edge[X[i]].push_back(Y[i]);
edge[Y[i]].push_back(X[i]);
}
dfs0(1, 1);
cin >> M;
for (int i = 0; i < M; ++i) {
int x, y, z; cin >> x >> y >> z;
path[lca(x, y)].push_back({z, {x, y}});
}
dfs(1, 1);
cout << A[1];
return 0;
}
