#include <bits/stdc++.h>

#define taskname ""
#define pb push_back
#define eb emplace_back
#define fi first
#define se second
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define for0(i, n) for (int i = 0; i < (int)(n); ++i)
#define for1(i, n) for (int i = 1; i <= (int)(n); ++i)
#define ford(i, n) for (int i = (int)(n) - 1; i >= 0; --i)
#define fore(i, a, b) for (int i = (int)(a); i <= (int)(b); ++i)

using namespace std;

typedef long long ll;
typedef long double ld;
typedef vector <int> vi;

template<class T> using v2d = vector <vector <T> >;
template<class T> bool uin(T &a, T b)
{
    return a > b ? (a = b, true) : false;
}
template<class T> bool uax(T &a, T b)
{
    return a < b ? (a = b, true) : false;
}

mt19937 rng(chrono::system_clock::now().time_since_epoch().count());

const int maxN = 1e5 + 10;
const ll inf = 1e18;

int n;
ll a[maxN], b[maxN], dp[maxN][2];
vi adj[maxN];

void dfs(int u, int p)
{
    dp[u][0] = dp[u][1] = 0;
    for (auto &v: adj[u])
    {
        if (v != p)
        {
            dfs(v, u);
            dp[u][0] += max(abs(a[u] - a[v]) + dp[v][0], abs(a[u] - b[v]) + dp[v][1]);
            dp[u][1] += max(abs(b[u] - a[v]) + dp[v][0], abs(b[u] - b[v]) + dp[v][1]);
        }
    }
}

void solve()
{
    cin >> n;
    for1(i, n)
    {
        cin >> a[i] >> b[i];
    }
    for1(i, n)
    {
        adj[i].clear();
    }
    for1(i, n - 1)
    {
        int u, v;
        cin >> u >> v;
        adj[u].eb(v);
        adj[v].eb(u);
    }
    dfs(1, 0);
    cout << max(dp[1][0], dp[1][1]) << "\n";
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int T = 1;
    cin >> T;
    while (T--)
    {
        solve();
    }
    return 0;
}
