#include <bits/stdc++.h>
using namespace std;
typedef pair<int,int> pii;
struct plan {
int a, b, c;
plan(int a, int b, int c):a(a),b(b),c(c){}
};
int n, m;
vector<int> lis[100100];
vector<plan> pl[100100];
int sz[100100];
map<int,int> *E[100100];
int D[100100];
int bias[100100];
int sps[100100][20];
int dep[100100];
void idfs(int here, int p, int d) {
int i;
sps[here][0] = p;
dep[here] = d;
for (i=0;i<lis[here].size();i++) {
int there = lis[here][i];
if (there==p) continue;
idfs(there,here,d+1);
}
}
void init() {
int i, j;
for (j=1;j<20;j++) {
for (i=0;i<n;i++) sps[i][j] = ((~sps[i][j-1])?sps[sps[i][j-1]][j-1]:-1);
}
}
int lca(int u, int v) {
if (dep[u]>dep[v]) swap(u,v);
int td = dep[v]-dep[u];
int i;
for (i=0;i<20;i++) {
if ((td>>i)&1) v = sps[v][i];
}
if (u==v) return u;
for (i=19;i>=0;i--) {
if (sps[u][i]==sps[v][i]) continue;
u=sps[u][i];v=sps[v][i];
}
return sps[u][0];
}
void dfs(int here, int p) {
int i, maxi = -1, t = -1, dsum = 0;
sz[here] = 1;
for (i=0;i<lis[here].size();i++) {
int there = lis[here][i];
if (there==p) continue;
dfs(there,here);
if (maxi<sz[there]) {
maxi=sz[there];
t=there;
}
dsum += D[there];
sz[here]+=sz[there];
}
if (~t) {
E[here] = E[t];
bias[here] = bias[t]+dsum-D[t];
}
else {
E[here] = new map<int,int>();
E[here]->insert(pii(here,0));
}
for (i=0;i<lis[here].size();i++) {
int there = lis[here][i];
if (there==p||there==t) continue;
map<int,int>::iterator it = E[there]->begin();
while(it!=E[there]->end()) {
E[here]->insert(pii((*it).first,(*it).second+bias[there]-bias[here]+dsum-D[there]));
it++;
}
E[there]->clear();
}
E[here]->insert(pii(here,dsum-bias[here]));
D[here] = dsum;
for (i=0;i<pl[here].size();i++) {
D[here] = max(D[here],pl[here][i].c+(*E[here])[pl[here][i].a]+bias[here]+(*E[here])[pl[here][i].b]+bias[here]-dsum);
}
}
int main() {
int i;
scanf("%d",&n);
for (i=0;i<n-1;i++) {
int x, y;
scanf("%d%d",&x,&y);
x--;y--;
lis[x].push_back(y);
lis[y].push_back(x);
}
idfs(0,-1,0);
init();
scanf("%d",&m);
for (i=0;i<m;i++) {
int a, b, c;
scanf("%d%d%d",&a,&b,&c);
a--;b--;
pl[lca(a,b)].push_back(plan(a,b,c));
}
dfs(0,-1);
printf("%d\n",D[0]);
return 0;
}
