//#pragma GCC optimize("Ofast,unroll-loops,no-stack-protector")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#include <bits/stdc++.h>
using namespace std;
#define debug(s) cout<< #s <<" = "<< s <<endl
#define all(v) (v).begin(), (v).end()
#define KeepUnique(v) (v).erase( unique(all(v)), v.end() )
#define MEMSET(a,val) memset(a, val, sizeof a)
#define PB push_back
#define endl '\n'
typedef long long ll;
inline int myrand(int l, int r) {
int ret = rand(); ret <<= 15; ret ^= rand();
if(ret < 0) ret = -ret; ret %= (r-l+1); ret += l;
return ret;
}
template <typename F, typename S>
ostream& operator << (ostream& os, const pair< F, S>& p) {
return os<<"(" <<p.first<<", "<<p.second<<")"; }
typedef pair<int, int> ii;
template<typename T> using min_pq =
priority_queue<T, vector<T>, greater<T> >;
//int dx[] = {-1, +0, +1, +0};
//int dy[] = {+0, +1, +0, -1};
const int maxn = 100005;
int n, m;
vector<int> g[maxn], paths[maxn], A, B, C;
int t[18][maxn], dp[maxn], sz[maxn], where[maxn], lvl[maxn], tym = 0;
ll S[maxn];
int dfs(int u, int par) {
sz[u] = 1;
where[u] = ++tym;
t[0][u] = par;
lvl[u] = par == -1 ? 0 : lvl[par] + 1;
for(int v : g[u]) {
if(par - v) {
dfs(v, u);
sz[u] += sz[v];
}
}
}
int __lca(int u, int v) {
if(lvl[u] > lvl[v]) swap(u, v);
int d = lvl[v] - lvl[u];
for(int i = 16; i >= 0; i--) {
if(d & (1 << i)) {
v = t[i][v];
}
}
if(u == v) return u;
for(int i = 16; i >= 0; i--) {
if(t[i][u] != t[i][v]) {
u = t[i][u];
v = t[i][v];
}
} return t[0][u];
}
void update(int u, int val) {
int l = where[u], r = where[u] + sz[u];
for(; l <= n; l += l & -l) S[l] += val;
for(; r <= n; r += r & -r) S[r] -= val;
}
int query(int u, int ret = 0) {
for(int p = where[u]; p > 0; p -= p & -p)
ret += S[p];
return ret;
}
int value(int u) {
return query(u) - (u != 1 ? query(t[0][u]) : 0);
}
int pathcost(int i) { // query path S[u] sum
int u = A[i], v = B[i];
int lca = __lca(u, v);
return query(u) + query(v) - query(lca) - (lca == 1 ? 0 : query(t[0][lca]));
}
void prep(int u, int par) {
for(int v : g[u]) {
if(v - par) {
prep(v, u);
update(u, dp[v]);
}
}
dp[u] = value(u);
for(int p : paths[u]) {
int ret = C[p] + pathcost(p);
dp[u] = max(dp[u], ret);
}
update(u, -dp[u]);
}
int32_t main () {
// freopen("in", "r", stdin);
scanf("%d", &n);
for(int i = 1; i < n; i++) {
int u, v; scanf("%d %d", &u, &v);
g[u].push_back(v);
g[v].push_back(u);
}
MEMSET(t, -1);
dfs(1, -1);
for(int p = 1; p <= 16; p++) {
for(int i = 1; i <= n; i++) {
int mid = t[p - 1][i];
if(mid != -1) t[p][i] = t[p - 1][mid];
}
}
scanf("%d", &m);
A.resize(m), B.resize(m), C.resize(m);
for(int i = 0; i < m; i++) {
scanf("%d %d %d", &A[i], &B[i], &C[i]);
paths[__lca(A[i], B[i])].push_back(i);
}
prep(1, -1);
printf("%d\n", dp[1]);
}
