#include <bits/stdc++.h>
using namespace std;
/// 17:03
const int Nmax = 1e5 + 5, lg = 18;
typedef long long ll;
int n, t[lg+2][Nmax], level[Nmax], In[Nmax], Out[Nmax], tmp;
ll sum[Nmax], dp[Nmax];
struct Plan
{
int x, y, c;
};
vector<int> v[Nmax];
vector<Plan> plan[Nmax];
class AIB
{
ll a[Nmax];
int ub(int x) { return (x&(-x)); }
public:
void update(int x, int y, ll val)
{
for(; x<=n; x+=ub(x)) a[x] += val;
for(++y; y<=n; y+=ub(y)) a[y] -= val;
}
ll query(int x)
{
ll ans = 0;
for(; x; x-=ub(x)) ans += a[x];
return ans;
}
} aib;
void dfs(int node)
{
int i;
for(i=1; i<=lg; ++i) t[i][node] = t[i-1][t[i-1][node]];
In[node] = ++tmp;
level[node] = level[t[0][node]] + 1;
for(auto it : v[node])
if(!level[it])
{
t[0][it] = node;
dfs(it);
}
Out[node] = tmp;
}
int lca(int x, int y)
{
if(level[x] < level[y]) swap(x, y);
int up = level[x] - level[y], i;
for(i=0; i<=lg; ++i)
if(up & (1<<i)) x = t[i][x];
if(x == y) return x;
for(i=lg; i>=0; --i)
if(t[i][x] != t[i][y]) x = t[i][x], y = t[i][y];
return t[0][x];
}
void solve(int node)
{
for(auto it : v[node])
if(it != t[0][node])
{
solve(it);
sum[node] += dp[it];
}
dp[node] = sum[node];
for(auto it : plan[node])
{
ll now = aib.query(In[it.x]) + aib.query(In[it.y]) + sum[node] + it.c;
dp[node] = max(dp[node], now);
}
aib.update(In[node], Out[node], sum[node] - dp[node]);
}
int main()
{
// freopen("input", "r", stdin);
cin.sync_with_stdio(false);
int i, x, y, m;
cin >> n;
for(i=1; i<n; ++i)
{
cin >> x >> y;
v[x].push_back(y);
v[y].push_back(x);
}
dfs(1);
cin >> m;
for(i=1; i<=m; ++i)
{
int money;
cin >> x >> y >> money;
plan[lca(x,y)].push_back({x, y, money});
}
solve(1);
cout << dp[1] << '\n';
return 0;
}
