#include<bits/stdc++.h>
using namespace std;
#define mid ((l+r)>>1)
#define maxs(a,b) (a=max(a,b))
#define pb push_back
const int MXN = 1e5+5;
const int LOG = 17;
int n, m, A[MXN], B[MXN], C[MXN];
vector<int> g[MXN];
int par[LOG][MXN], stt[MXN], fnt[MXN], timer;
void dfs(int v) {
stt[v] = timer++;
for(int i=1; i<LOG; i++)
par[i][v] = par[i-1][par[i-1][v]];
for(int u : g[v])
if(u^par[0][v])
par[0][u] = v,
dfs(u);
fnt[v] = timer;
}
inline bool is_anc(int u, int v) { return stt[u]<=stt[v] && fnt[v]<=fnt[u]; }
inline int LCA(int u, int v) {
if(is_anc(u,v)) return u;
for(int i=LOG-1; i>=0; i--)
if(par[i][u] && !is_anc(par[i][u], v))
u = par[i][u];
return par[0][u];
}
int fen[MXN];
inline void updx(int s, int e, int x) {
for(++s; s<MXN; s+=s&-s) fen[s] += x;
for(++e; e<MXN; e+=e&-e) fen[e] -= x;
}
inline int getx(int p) {
int res=0;
for(++p; p; p-=p&-p) res += fen[p];
return res;
}
vector<int> Q[MXN];
int dp[MXN];
void DFS(int v) {
int sum=0;
for(int u : g[v])
if(u^par[0][v])
DFS(u),
sum += dp[u];
dp[v] = sum;
for(int i : Q[v])
maxs(dp[v], getx(stt[A[i]])+getx(stt[B[i]])+C[i]+sum);
updx(stt[v], fnt[v], sum-dp[v]);
}
int32_t main() {
cin.tie(0); cout.tie(0); ios_base::sync_with_stdio(0);
cin >> n;
for(int i=0, u,v; i<n-1; i++) {
cin >> u >> v;
g[u].pb(v);
g[v].pb(u);
}
dfs(1);
int m;
cin >> m;
for(int i=1; i<=m; i++) {
cin >> A[i] >> B[i] >> C[i];
Q[LCA(A[i], B[i])].pb(i);
}
DFS(1);
cout << dp[1] << '\n';
return 0;
}
