#include <bits/stdc++.h>
using namespace std;
#define REP(i,n) for(int (i)=0;(i)<(int)(n);(i)++)
#define REPO(i,n) for(int (i)=1; (i)<=(int)(n); (i)++)
#define SZ(v) ((int)(v).size())
#define ALL(v) (v).begin(),(v).end()
#define one first
#define two second
typedef long long ll;
typedef pair<int, int> pi;
const int INF = 0x3f2f1f0f;
const ll LINF = 1ll * INF * INF;
const int MAX_N = 1e5 + 10, LOG_N = 20;
int N, Q, P[LOG_N][MAX_N], D[MAX_N], St[MAX_N], En[MAX_N], Ix;
vector<int> Ed[MAX_N];
int getLCA(int a, int b) {
if(D[a] < D[b]) swap(a, b);
for(int p=0; p<LOG_N; p++) if((1<<p) & (D[a]-D[b])) a = P[p][a];
if(a == b) return a;
for(int p=LOG_N-1; p>=0; p--)
if(P[p][a] != P[p][b])
a = P[p][a], b = P[p][b];
a = P[0][a];
return a;
}
void dfs(int v, int p) {
St[v] = Ix++; P[0][v] = p; D[v] = D[p] + 1;
for(int w : Ed[v]) if(w != p) dfs(w, v);
En[v] = Ix-1;
}
struct IDX {
int P; vector<int> val;
IDX() {}
IDX(int n) {
for(P=1; P<n; P<<=1);
val = vector<int>(2*P, 0);
}
void update(int a, int b, int v) {
a += P; b += P;
while(a<=b) {
if(a%2==1) val[a++] += v;
if(b%2==0) val[b--] += v;
a >>= 1; b >>= 1;
}
}
int getAll(int v) {
int res = val[v += P];
while(v >>= 1) res += val[v];
return res;
}
}idx;
typedef tuple<int, int, int> ti;
vector<ti> Qs[MAX_N];
int getAns(int v, int p) {
int notUse = 0;
for(int w : Ed[v]) if(w != p) {
notUse += getAns(w, v);
}
int use = notUse;
for(ti &e : Qs[v]) {
int x, y, c; tie(x, y, c) = e;
use = max(use, notUse + idx.getAll(St[x]) + idx.getAll(St[y]) + c);
}
idx.update(St[v], En[v], notUse - use);
// printf("%d : %d %d\n", v, notUse, use);
return use;
}
int main() {
cin >> N;
REP(i, N-1) {
int x, y; scanf("%d%d", &x, &y);
Ed[x].push_back(y); Ed[y].push_back(x);
}
dfs(1, 0);
idx = IDX(Ix);
for(int p=1; p<LOG_N; p++) for(int i=1; i<=N; i++) P[p][i] = P[p-1][P[p-1][i]];
cin >> Q;
while(Q--) {
int x, y, c; scanf("%d%d%d", &x, &y, &c);
// printf("[%d %d %d]\n", x, y, c);
int l = getLCA(x, y);
Qs[l].push_back(ti(x, y, c));
}
printf("%d\n", getAns(1, 0));
return 0;
}
