//Dedicated to my love, ivaziva
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
#define pii pair<int,int>
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define sz(a) ((int)a.size())
const int N=1e6+5;
struct node {
int a, b, c;
};
int n, m, up[N][20], dep[N], tin[N], tout[N], tajm=1, ft[N];
vector<int> g[N];
ll dp[N][2];
vector<node> pom[N];
void dfs(int x, int p) {
dep[x]=dep[p]+1;
tin[x]=tajm++;
up[x][0]=p;
for (int i=1; i<20; i++)
up[x][i]=up[up[x][i-1]][i-1];
for (int u:g[x]) {
if (u!=p)
dfs(u, x);
}
tout[x]=tajm++;
}
int raise(int x, int y) {
int z=0;
while (y) {
if (y&1)
x=up[x][z];
z++;
y>>=1;
}
return x;
}
array<int, 3> lca(int a, int b) {
if (dep[a]>dep[b])
swap(a, b);
int x=dep[b]-dep[a];
int ob=b;
b=raise(b, x);
if (a==b)
return {a, raise(ob, x-1), -1};
for (int i=19; i>=0; i--) {
if (up[a][i]!=up[b][i]) {
a=up[a][i];
b=up[b][i];
}
}
return {up[a][0], a, b};
}
void modify(int i, int val) {
while (i<N) {
ft[i]+=val;
i+=i&(-i);
}
}
ll get(int i) {
int ret=0;
while (i) {
ret+=ft[i];
i-=i&(-i);
}
return ret;
}
int main () {
ios::sync_with_stdio(false), cin.tie(0);
cin >> n;
for (int i=1; i<n; i++) {
int u, v;
cin >> u >> v;
g[u].pb(v);
g[v].pb(u);
}
dfs(1, 0);
int q;
cin >> q;
while (q--) {
int a, b, c;
cin >> a >> b >> c;
array<int, 3> LCA=lca(a, b);
pom[LCA[0]].pb({a, b, c});
}
for (int i=1; i<=n; i++)
dp[i][0]=0, dp[i][1]=0;
pii ord[n];
for (int i=1; i<=n; i++)
ord[i-1]=make_pair(dep[i], i);
sort(ord, ord+n);
reverse(ord, ord+n);
for (int i=0; i<n; i++) {
int x=ord[i].second;
for (int u:g[x]) {
if (u!=up[x][0])
dp[x][0]+=dp[u][1];
}
for (auto z:pom[x])
dp[x][1]=max(dp[x][1], dp[x][0]+get(tin[z.a])+get(tin[z.b])-2*get(tin[x])+z.c);
dp[x][1]=max(dp[x][1], dp[x][0]);
modify(tin[x], dp[x][0]-dp[x][1]);
modify(tout[x], dp[x][1]-dp[x][0]);
}
cout << max(dp[1][0], dp[1][1]) << '\n';
}
