#include <bits/stdc++.h>
using namespace std;
#define ii pair <int, int>
#define ff first
#define ss second
#define bit(i) (1 << (i))
#define fto(i, a, b) for (int i = (a); i <= (b); ++i)
#define fdto(i, a, b) for (int i = (a); i >= (b); --i)
#define flto(i, a, b) for (int i = (a); (1 << i) <= (b); ++i)
#define pb push_back
#define pf push_front
#define endl "\n"
#define oo (int)(1e9 + 7)
#define maxN 100005
#define l(s) s.length()
#define vi vector <int>
#define vii vector <ii>
#define fat(x, y) for (auto x : y)
#define fit(x, y) for (int x : y)
#define fiit(x, y) for (ii x : y)
#define EPS 1e-9
#define pi (acos(-1))
#define ll long long
int n, m, tme;
vi ke[maxN];
vector<pair<int, ii>> path[maxN];
int sta[maxN], fin[maxN], h[maxN];
int par[20][maxN];
ll bt[maxN], dp[maxN];
void ud(int i, ll x) {
for (; i <= n; i += (i& -i)) bt[i] += x;
}
ll qry(int i) {
ll res = 0;
for (; i; i -= (i & -i)) res += bt[i];
return res;
}
void pre_dfs(int u) {
flto(j, 1, h[u]) par[j][u] = par[j-1][par[j-1][u]];
sta[u] = ++tme;
for (int v : ke[u]) if (v != par[0][u]) {
par[0][v] = u;
h[v] = h[u] + 1;
pre_dfs(v);
}
fin[u] = tme;
}
int lca(int u, int v) {
if (h[u] < h[v]) swap(u, v);
fdto(i, 17, 0) if (h[u] - bit(i) >= h[v]) u = par[i][u];
if (u == v) return u;
fdto(i, 17, 0) if (par[i][u] != par[i][v]) u = par[i][u], v = par[i][v];
return par[0][u];
}
void dfs(int u) {
ll sum = 0;
for (int v : ke[u]) if (v != par[0][u]) {
dfs(v);
sum += dp[v];
}
dp[u] = sum;
for (auto tmp : path[u]) {
auto [x, y] = tmp.ss;
dp[u] = max(dp[u], qry(sta[x]) + qry(sta[y]) + tmp.ff + sum);
}
ud(sta[u], sum - dp[u]);
ud(fin[u] + 1, dp[u] - sum);
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr); cout.tie(nullptr);
cin >> n;
fto(i, 1, n-1) {
int u, v; cin >> u >> v;
ke[u].pb(v);
ke[v].pb(u);
}
pre_dfs(1);
cin >> m;
fto(i, 1, m) {
int u, v, c; cin >> u >> v >> c;
path[lca(u, v)].pb({c, {u, v}});
}
dfs(1);
cout << dp[1] << endl;
return 0;
}
