#include <bits/stdc++.h>
using namespace std;
const int MAX = 1e5+10;
const int LG = 18;
int n, de[MAX], pa[LG][MAX], su[MAX], dn[MAX];
vector<int> G[MAX];
void dfs1(int v, int p, int d=1){
de[v] = d, su[v] = 1;
for(int x:G[v]){
if(x==p) continue;
pa[0][x] = v;
for(int i=1; i<LG; i++) pa[i][x] = pa[i-1][pa[i-1][x]];
dfs1(x,v,d+1); su[v]+=su[x];
if(su[dn[v]]<su[x]) dn[v]=x;
}
}
int lca(int u, int v){
if(de[u]<de[v]) swap(u,v);
for(int i=LG-1; i>=0; i--) if(de[u]-(1<<i)>=de[v]) u = pa[i][u];
if(u==v) return u;
for(int i=LG-1; i>=0; i--) if(pa[i][u]!=pa[i][v]) u = pa[i][u], v = pa[i][v];
return pa[0][u];
}
class Seg_t{
int n; vector<int> T; // sum
void upt(int v, int s, int e, int p, int x){
if(p<s || e<p) return;
if(s==e){ T[v]=x; return; }
upt(v*2, s, (s+e)/2, p, x); upt(v*2+1, (s+e)/2+1, e, p, x);
T[v] = T[v*2] + T[v*2+1];
}
int sum(int v, int s, int e, int l, int r){
if(e<l || r<s) return 0;
if(l<=s && e<=r) return T[v];
return sum(v*2,s,(s+e)/2,l,r) + sum(v*2+1,(s+e)/2+1,e,l,r);
}
public:
Seg_t(int sz): n(sz) { // [0, n)
int k=1; while(k<sz) k<<=1;
T.resize(k<<1, 0);
}
Seg_t(): Seg_t(0) {}
void upt(int p, int x){ upt(1,0,n-1,p,x); }
int sum(int l, int r){ return sum(1,0,n-1,l,r); }
int val(int p){ return sum(p,p); }
};
class HLD_t{
Seg_t Seg[MAX]; int rt[MAX], sz[MAX];
void dfs0(int v, int p, int c){
rt[v] = c; sz[c]++;
for(int x:G[v]) if(x!=p)
dfs0(x, v, (x==dn[v] ? c : x));
}
int sum_u(int x, int v){ // [x,v]
int res = 0;
for(int t, r; de[x]>=de[v]; x=pa[0][t]){
r = rt[x], t = (de[r]<de[v] ? v : r);
res += Seg[r].sum(de[t]-de[r], de[x]-de[r]);
}
return res;
}
int val(int v){ return Seg[rt[v]].val(de[v]-de[rt[v]]); }
public:
void init(){
dfs0(1,0,1);
for(int i=1; i<=n; i++) Seg[i] = Seg_t(sz[i]);
}
void upt(int v, int x){
Seg[rt[v]].upt(de[v]-de[rt[v]], x);
}
int sum_p(int x, int y, int p){ return sum_u(x,p) + sum_u(y,p) - val(p); }
} HLD;
vector<int> plan[MAX];
int m, X[MAX], Y[MAX], C[MAX];
int D[MAX], S[MAX];
void dfs2(int v, int p){
for(int x:G[v]){
if(x==p) continue;
dfs2(x,v); S[v]+=D[x];
}
D[v] = S[v]; HLD.upt(v, S[v]);
for(int idx:plan[v]){
int x=X[idx], y=Y[idx], c=C[idx];
// 이걸 쓰는 경우: now = c + sum(S[x...y]) - sum(D[x...v)) - sum(D[y...v))
// (let D[v]=0) now = c + sum(S[x...y]) - sum(D[x...y])
int now = c + HLD.sum_p(x,y,v);
D[v] = max(now, D[v]);
}
HLD.upt(v, S[v]-D[v]);
}
int main(){
ios::sync_with_stdio(0); cin.tie(0);
cin>>n;
for(int i=1; i<n; i++){
int u,v; cin>>u>>v;
G[u].push_back(v);
G[v].push_back(u);
}
dfs1(1,0);
HLD.init();
cin>>m;
for(int i=1; i<=m; i++){
cin>>X[i]>>Y[i]>>C[i];
plan[lca(X[i], Y[i])].push_back(i);
}
dfs2(1,0);
cout<<D[1]<<'\n';
return 0;
}
