cf-f

#include <bits/stdc++.h>
#define ios std::ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define clr cin.ignore(numeric_limits<streamsize>::max(), '\n');
#define ll long long
#define ull unsigned long long
#define ui unsigned int
#define Sort(v) sort(v.begin(),v.end());
#define rsort(v) sort(v.begin(),v.end(), greater<int> ());
#define pb push_back
#define uset unordered_set
#define umap unordered_map
#define pll pair<long long, long long>
#define pii pair<int, int>
#define vi vector<int>
#define vll vector<long long>
#define Max(arr,n) *max_element(arr, arr+n)
#define lb(v,x) (lower_bound(v.begin(),v.end(),x) - v.begin())
#define ub(v,x) (upper_bound(v.begin(),v.end(),x) - v.begin())

using namespace std;

template <typename T>
void printv(vector<T> v){
    for (int i = 0; i < v.size(); i++) cout << v[i] << " ";
    cout << '\n';
}

template <typename T>
void printA(T arr[], int n){
    for (int i = 0; i < n; i++) cout << arr[i] << " ";
    cout << '\n';
}

template <typename T>
void print(T var){
    cout << var << '\n';
}

template <typename T>
vector<T> v_input(ll n){
    vector<T> a(n);
    for (ll i = 0; i < n; i++) cin >> a[i];
    return a;
}

ll t;

void dfs(ll node, vll graph[], vector<bool> visited, vll l, vll r, vll ans[]) {
    if (visited[node]) return;
    visited[node]=true;
    for (ll nd : graph[node])
    {
        if (!visited[nd]) {
            dfs(nd, graph, visited, l, r, ans);
            ans[node][0] += max(abs(l[node]-l[nd]) + ans[nd][0], abs(l[node]-r[nd]) + ans[nd][1]);
            ans[node][1] += max(abs(r[node]-l[nd]) + ans[nd][0], abs(r[node]-r[nd]) + ans[nd][1]);
        }
    }

}

void solve() {
    ll n;
    cin >> n;
    vll l(n+1), r(n+1);
    for (int i = 1; i < n+1; i++)
    {
        cin >> l[i] >> r[i];
    }
    ll x, y;
    vll graph[n+1];
    for (int i = 0; i < n-1; i++)
    {
        cin >> x >> y;
        graph[x].pb(y);
        graph[y].pb(x);
    }
    vll ans[n+1];
    for (int i = 0; i < n+1; i++)
    {
        ans[i] = vll(2, 0);
    }
    vector<bool> visited(n+1, false);
    dfs(1, graph, visited, l, r, ans);
    print(max(ans[1][0], ans[1][1]));
}

int main()
{
    ios;
    cin >> t;
    while (t--)
    {
        solve();
    }
}