#include <bits/stdc++.h>
#define ll long long
using namespace std;
const int N = 1e5+10, LOG = 20;
vector<array<int, 3>> paths[N];
ll in[N], out[N], d[N], L[N][LOG], t[2*N][2], sum[N], dp[N];
ll n, m;
vector<int> edges[N];
void dfs(int x, int p) {
static int timer = 0;
in[x] = ++timer;
L[x][0] = p;
d[x] = d[p] + 1;
for(int i = 1; i < LOG; ++i) {
L[x][i] = L[L[x][i - 1]][i - 1];
}
for(int to : edges[x]) {
if(to != p) {
dfs(to, x);
}
}
out[x] = ++timer;
}
bool is_anc(int x, int y) {
return !x || in[x] <= in[y] && out[x] >= out[y];
}
int lca(int x, int y) {
if(is_anc(x, y)) return x;
if(is_anc(y, x)) return y;
for(int i = LOG-1; ~i; --i) {
if(!is_anc(L[x][i], y)) {
x = L[x][i];
}
}
return L[x][0];
}
int dist(int x, int y) {
return abs(d[x] - d[y]);
}
int find_anc(int x, int d) {
for(int bit = 0; bit < LOG; ++bit) {
if(d >> bit & 1) x = L[x][bit];
}
return x;
}
void maxi(ll &x, ll y) {
if(x < y) x = y;
}
void update(ll x, ll v, ll id) {
for(; x <= 2*n; x += x & -x) {
t[x][id] += v;
}
}
ll query(ll x, ll id) {
ll sum = 0;
for(; x > 0; x -= x & -x) {
sum += t[x][id];
}
return sum;
}
ll query(ll l, ll r, ll id) {
return query(r, id) - query(l-1, id);
}
void solve(int x, int p) {
for(int to : edges[x]) {
if(to != p) {
solve(to, x);
sum[x] += dp[to];
}
}
dp[x] = sum[x];
for(auto &q : paths[x]) {
int a = q[0];
int b = q[1];
int c = q[2];
ll sum0 = query(in[x], in[a], 0);
ll sum1 = query(in[x], in[b], 0);
ll s = sum0 + sum1 + sum[x];
if(a != x) {
int pa = find_anc(a, dist(x, a) - 1);
s -= query(in[pa], in[a], 1);
}
if(b != x) {
int pb = find_anc(b, dist(x, b) - 1);
s -= query(in[pb], in[b], 1);
}
maxi(dp[x], s + c);
}
update(in[x], sum[x], 0);
update(out[x], -sum[x], 0);
update(in[x], dp[x], 1);
update(out[x], -dp[x], 1);
}
int main() {
ios::sync_with_stdio(0); cin.tie(0);
cin >> n;
for(int i = 0; i < n-1; ++i) {
int u, v; cin >> u >> v;
edges[u].push_back(v);
edges[v].push_back(u);
}
dfs(1, 0);
cin >> m;
for(int i = 0; i < m; ++i) {
int u, v, c; cin >> u >> v >> c;
paths[lca(u, v)].push_back({u, v, c});
}
solve(1, 0);
cout << dp[1] << endl;
}
