#include<bits/stdc++.h>
using namespace std;
const int maxn = 1e5 + 5;
const int mlog = 17;
int n,m;
vector<int> way[maxn];
vector<tuple<int,int,int>> have[maxn];
int cur, st[maxn], ft[maxn];
int h[maxn], par[maxn][20];
int tree[maxn*4];
int dp[maxn];
void dfs(int u, int last) {
st[u] = ++cur;
h[u] = h[last] + 1;
par[u][0] = last;
for(int i=1;i<=mlog;i++) par[u][i] = par[par[u][i-1]][i-1];
for(auto v : way[u]) {
if(v==last) continue;
dfs(v,u);
}
ft[u] = cur;
}
int lca(int u, int v) {
if(h[u]<h[v]) swap(u,v);
for(int i=mlog;i>=0;i--) if(h[par[u][i]]>=h[v]) u = par[u][i];
if(u==v) return u;
for(int i=mlog;i>=0;i--) {
if(par[u][i]!=par[v][i]) {
u = par[u][i]; v = par[v][i];
}
}
return par[u][0];
}
void update(int pos, int l, int r, int x, int y, int val) {
if(l>r || r<x || y<l) return ;
if(x<=l && r<=y) {
tree[pos] += val;
return ;
}
int mid = (l+r)/2;
update(pos<<1,l,mid,x,y,val); update(pos<<1|1,mid+1,r,x,y,val);
}
int query(int pos, int l, int r, int x) {
if(l>r || r<x || x<l) return 0;
if(l==r) return tree[pos];
int mid = (l+r)/2;
return tree[pos] + query(pos<<1,l,mid,x) + query(pos<<1|1,mid+1,r,x);
}
void solve(int u, int last) {
int sum = 0;
//solve child
for(auto v : way[u]) {
if(v==last) continue;
solve(v, u);
sum += dp[v];
}
//solve u
dp[u] = sum;
for(auto t : have[u]) {
int x,y,val;
tie(x,y,val) = t;
int change = query(1,1,n,st[x]) + query(1,1,n,st[y]);
dp[u] = max(dp[u], sum + val + change);
}
//update subtree u
update(1,1,n,st[u],ft[u],-dp[u]+sum);
}
int main() {
scanf("%d",&n);
for(int i=1;i<=n-1;i++) {
int u,v; scanf("%d%d",&u,&v);
way[u].push_back(v); way[v].push_back(u);
}
dfs(1,0);
scanf("%d",&m);
for(int i=1;i<=m;i++) {
int u,v,val; scanf("%d%d%d",&u,&v,&val);
have[lca(u,v)].emplace_back(u,v,val);
}
solve(1,0);
printf("%d",dp[1]);
}
