F

#include <bits/stdc++.h>


using namespace std;

//#define int long long

const long long INF = 1e18 + 7;
const int MAXN = 1e5 + 10;
const int N = 1e5 + 10;

long long dp[2][MAXN];
array<vector<int>, MAXN> g;
array<pair<int, int>, MAXN> val;

void dfs(int v, int p) {
    dp[0][v] = dp[1][v] = 0;
    for (auto to: g[v]) {
        if (to == p) {
            continue;
        }
        dfs(to, v);
        dp[0][v] += max(dp[0][to] + abs(val[v].first - val[to].first), dp[1][to] + abs(val[v].first - val[to].second));
        dp[1][v] += max(dp[0][to] + abs(val[v].second - val[to].first), dp[1][to] + abs(val[v].second - val[to].second));
    }
}

void solve() {
    int n;
    cin >> n;
    for (int i = 0; i < n; ++i) {
        cin >> val[i].first >> val[i].second;
    }
    fill(g.begin(), g.begin() + n, vector<int>());
    for (int i = 0; i < n - 1; ++i) {
        int u, v;
        cin >> u >> v;
        --u, --v;
        g[u].emplace_back(v);
        g[v].emplace_back(u);
    }

    dfs(0, -1);

    cout << max(dp[0][0], dp[1][0]) << '\n';
}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);

    int tt = 1;
    cin >> tt;
    while (tt--) {
        solve();
    }
}