#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pi pair<int, int>
#define pii pair<int, pi>
#define fi first
#define se second
#ifdef _WIN32
#define getchar_unlocked _getchar_nolock
#endif
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
int ft[500005], n, S[100005], E[100005], dp[100005], par[20][100005], dep[100005];
void upd(int l, int r, int v){
r++;
for(;l<=n;l+=(l & -l))ft[l] += v;
for(;r <= n; r += (r & -r))ft[r] -= v;
}
int qry(int p){
int res = 0;
for(;p;p-=(p & -p))res += ft[p];
return res;
}
vector <int> adj[100005];
vector <pii> stuf[100005];
int cnt = 1;
void dfs(int x, int p, int d){
S[x] = cnt++;
par[0][x] = p;
for(int i = 1; i <= 19; i++)par[i][x] = par[i-1][par[i-1][x]];
dep[x] = d;
for(auto i : adj[x])if(i != p)dfs(i, x, d + 1);
E[x] = cnt - 1;
}
int lca(int u, int v){
if(dep[u] > dep[v])swap(u, v);
int df = dep[v] - dep[u];
for(int i=0;i<=19;i++)if(df >> i & 1)v = par[i][v];
if(u == v)return u;
for(int i=19;i>=0;i--)if(par[i][u] != par[i][v])u = par[i][u], v = par[i][v];
return par[0][u];
}
void proc(int x, int p){
for(auto i : adj[x]){
if(i != p){
proc(i, x);
}
}
int sm = 0;
for(auto i : adj[x]){
if(i != p){
upd(S[x], E[x], dp[i]);
upd(S[i], E[i], -dp[i]);
sm += dp[i];
}
}
int ans = sm;
for(auto i : stuf[x]){
//cout << x << ' ' << i.se.fi << ' ' << i.se.se << ' ' << qry(S[i.se.fi]) << ' ' << qry(S[i.se.se]) << '\n';
ans = max(ans, i.fi + qry(S[i.se.fi]) + qry(S[i.se.se]) - sm);
}
//cout << x << ' ' << sm << ' ' << ans << '\n';
dp[x] = ans;
}
void solve(){
cin >> n;
for(int i=1;i<n;i++){
int a, b; cin >> a >> b;
adj[a].push_back(b);
adj[b].push_back(a);
}
dfs(1, -1, 1);
int m; cin >> m;
while(m--){
int a, b, c; cin >> a >> b >> c;
stuf[lca(a, b)].push_back({c, {a, b}});
}
proc(1, -1);
cout << dp[1];
}
main(){
ios::sync_with_stdio(0);cin.tie(0);
int tc = 1;
//cin >> tc;
for(int tc1=1;tc1<=tc;tc1++){
// cout << "Case #" << tc1 << ": ";
solve();
}
}
