#include <bits/stdc++.h>
#define ll long long
#define ld long double
#define ull unsigned long long
#define pb push_back
#define pll pair<ll, ll>
#define pii pair<int, int>
#define fi first
#define se second
using namespace std;
const int N = 2e5+5;
const int M = (1<<17);
const ll inf = 1e15;
const int mod = 1e9+7;
int n, t, k, a[N], c[N], d[N], m, P[N][19], h[N], in[N], out[N];
ll ans, tong, b[N], dp[N], fe[N];
string s;
struct node
{
int val, x, y;
node(){}
node(int _val, int _x, int _y)
{
val = _val;
x = _x;
y = _y;
}
bool operator < (const node& u) const
{
return x > u.x;
}
};
vector<node> g[N];
vector<int> adj[N];
void add(int id, ll x)
{
for(; id <= n; id += id & -id)fe[id] += x;
}
void add(int l, int r, ll x)
{
add(l, x);
add(r+1, -x);
}
ll get(int id)
{
ll total = 0;
for(; id; id -= id & -id)total += fe[id];
return total;
}
void dfs(int u, int p = 0)
{
in[u] = ++k;
for(int v: adj[u])
{
if(v == p)continue;
h[v] = h[u]+1;
P[v][0] = u;
for(int i = 1; i <= 18; i ++)P[v][i] = P[P[v][i-1]][i-1];
dfs(v, u);
}
out[u] = k;
}
int lca(int u, int v)
{
if(h[u] < h[v])swap(u, v);
int log = log2(h[u]);
for(int i = log; i >= 0; i --)if(h[u] >= h[v]+(1<<i))u = P[u][i];
if(u == v)return u;
for(int i = log; i >= 0; i --)
{
if(P[u][i] && P[u][i] != P[v][i])
{
u = P[u][i];
v = P[v][i];
}
}
return P[u][0];
}
void cal(int u, int p = 0)
{
for(int v: adj[u])
{
if(v == p)continue;
cal(v, u);
add(in[u], out[u], dp[v]);
add(in[v], out[v], -dp[v]);
}
dp[u] = get(in[u]) - get(in[p]);
for(node t: g[u])
{
dp[u] = max(dp[u], get(in[t.x]) + get(in[t.y]) - get(in[u]) - get(in[p]) + t.val);
}
}
void sol()
{
cin >> n;
for(int i = 1; i < n; i ++)
{
int x, y;
cin >> x >> y;
adj[x].pb(y);
adj[y].pb(x);
}
dfs(1);
cin >> m;
while(m -- > 0)
{
int x, y, z;
cin >> x >> y >> k;
z = lca(x, y);
g[z].pb(node(k, x, y));
}
cal(1);
cout << dp[1];
}
int main()
{
cin.tie(0);
cout.tie(0);
ios_base::sync_with_stdio(0);
#define task "test"
if(fopen(task".inp", "r"))
{
freopen(task".inp", "r", stdin);
freopen(task".out", "w", stdout);
}
int ntest = 1;
//cin >> ntest;
while(ntest -- > 0)
sol();
}
