#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define FOR(i, a, b) for (int i = (a), _b = (b); i <= _b; i++)
#define FORD(i, b, a) for (int i = (b), _a = (a); i >= _a; i--)
#define pa pair<ll, ll>
#define fi first
#define se second
#define bit(mask, j) ((mask >> j) & 1)
const ll mod = 1e9 + 7;
const ll INF = 1e18;
//--------------------------------------------------------------------
const ll N = 1e5 + 10;
ll n;
ll m;
vector<ll> g[N];
ll up[N][19], h[N];
ll in[N], en[N];
ll timedfs;
void dfs(ll u, ll p) {
in[u] = ++timedfs;
for(auto v : g[u]) {
if(v == p) continue;
h[v] = h[u] + 1;
up[v][0] = u;
FOR(i, 1, 18) up[v][i] = up[up[v][i - 1]][i - 1];
dfs(v, u);
}
en[u] = timedfs;
}
ll get(ll u, ll k) {
for(int j = 0; (1 << j) <= k; j++) {
if(bit(k, j)) u = up[u][j];
}
return u;
}
ll lca(ll u, ll v) {
if(h[u] < h[v]) swap(u, v);
u = get(u, h[u] - h[v]);
if(u == v) return u;
FORD(i, 18, 0) {
if(up[u][i] != up[v][i]) {
u = up[u][i];
v = up[v][i];
}
}
return up[u][0];
}
struct state {
ll u, v, c;
};
vector<state> vc[N];
ll dp[N];
const int maxbit = 1e5 + 10;
ll BIT[maxbit], BIT2[maxbit];
void update(int x, ll val, ll val2) {
while(x <= n) {
BIT[x] += val;
BIT2[x] += val2;
x += x & -x;
}
}
ll getsum(int x) {
ll res = 0;
while(x > 0) {
res += BIT[x];
x -= x & -x;
}
return res;
}
ll getdp(int x) {
ll res = 0;
while(x > 0) {
res += BIT2[x];
x -= x & -x;
}
return res;
}
void update_lr(int l, int r, ll val, ll val2 ) {
update(l, val, val2);
update(r + 1, -val, -val2);
}
int walk(int x, int _n) {
int pos = 0;
int LG = __lg(_n);
FORD(j, LG, 0) {
if(pos + (1 << j) <= _n && BIT[pos + (1 << j)] < x) {
pos += (1 << j);
x -= BIT[pos];
}
}
return pos + 1;
}
void calc(ll u, ll p) {
ll sum_dp = 0;
for(auto v : g[u]) {
if(v == p) continue;
calc(v, u);
sum_dp += dp[v];
}
dp[u] = sum_dp;
for(auto e : vc[u]) {
ll sum = getsum(in[e.u]) + getsum(in[e.v]) + sum_dp;
ll rem = getdp(in[e.u]) + getdp(in[e.v]);
dp[u] = max(dp[u], sum - rem + e.c);
}
update_lr(in[u], en[u], sum_dp, dp[u]);
}
void hbmt() {
cin >> n;
FOR(i, 1, n - 1) {
ll u, v;
cin >> u >> v;
g[u].push_back(v);
g[v].push_back(u);
}
dfs(1, 0);
cin >> m;
FOR(i, 1, m) {
ll u, v, c;
cin >> u >> v >> c;
ll p = lca(u, v);
vc[p].push_back({u, v, c});
}
calc(1, 0);
cout << dp[1];
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);cout.tie(0);
#define NAME "hbmt"
if(fopen(NAME".inp", "r")) {
freopen(NAME".inp", "r", stdin);
freopen(NAME".out", "w", stdout);
}
//int t;cin>>t;while(t--)
hbmt();
return 0;
}
