#include<bits/stdc++.h>
#define int long long
#define fi first
#define se second
#define MULT_TEST 1
using namespace std;
typedef long double ldb;
typedef unsigned long long ull;
const int INF = 0x3f3f3f3f;
const int MOD = 998244353;
const int N = 100005;
int f[N], x[N], y[N];
bool vis[N];
vector<int> e[N];
struct node {
    int a, b, id;
    bool operator < (const Node &A) const {
        if (a > b && A.a <= A.b) return 1;
        if (a <= b && A.a > A.b) return 0;
        if (a > b && A.a > A.b) return b <= A.b;
        else return a > A.a;
    }
};
struct dsu {
    vector<int> fa;
    dsu(int n) : fa(n + 2) { iota(fa.begin(), fa.end(), 0); };
    inline int Find(int r) {
        while (r != fa[r]) r = fa[r] = fa[fa[r]];
        return r;
    }
    inline bool Merge(int x, int y) {
        x = Find(x); y = Find(y);
        if (x == y) return true;
        else return fa[y] = x, false;
    }
};
inline int read() {
    int w = 0, f = 1;
    char ch = getchar();
    while (ch < '0' || ch > '9') {
        if (ch == '-') f = -1;
        ch = getchar();
    }
    while (ch >= '0' && ch <= '9') {
        w = (w << 1) + (w << 3) + ch - 48;
        ch = getchar();
    }
    return w * f;
}
inline void DFS(int x) {
    for (auto u : e[x]) {
        if (u == f[x]) continue;
        f[u] = x, DFS(u);
    }
}
inline void Solve() {
    int n;
    n = read();
    priority_queue<node> q;
    vis[1] = 1;
    for (int i = 2; i <= n; i++) {
        x[i] = read(), y[i] = read();
        q.push((node){x[i], y[i], i});
    }
    for (int i = 1; i < n; i++) {
        int u = read(), v = read();
        e[u].push_back(v), e[v].push_back(u);
    }
    DFS(1);
    dsu A(n);
    while (!q.empty()) {
        auto [a, b, id] = q.top(); q.pop();
        if (vis[id] || a != x[id] || b != y[id]) continue;
        vis[id] = 1;
        int top = A.Find(f[id]);
        x[top] = max(x[top], x[top] - y[top] + x[id]);
        y[top] = y[top] - x[id] + y[id];
        q.push((node){x[top], y[top], top});
        A.fa[id] = top;
    }
    printf("%lld\n", x[1]);
    for (int i = 1; i <= n; i++) 
        e[i].clear(), f[i] = x[i] = y[i] = vis[i] = 0;
}
signed main() {
    int _ = 1;
#if MULT_TEST
    _ = read();
#endif 
    while (_--) Solve();
    return 0;
}

answer.code:17:28: error: ‘Node’ does not name a type; did you mean ‘node’?
   17 |     bool operator < (const Node &A) const {
      |                            ^~~~
      |                            node
answer.code: In member function ‘bool node::operator<(const int&) const’:
answer.code:18:24: error: request for member ‘a’ in ‘A’, which is of non-class type ‘const int’
   18 |         if (a > b && A.a <= A.b) return 1;
      |                        ^
answer.code:18:31: error: request for member ‘b’ in ‘A’, which is of non-class type ‘const int’
   18 |         if (a > b && A.a <= A.b) return 1;
      |                               ^
answer.code:19:25: error: request for member ‘a’ in ‘A’, which is of non-class type ‘const int’
   19 |         if (a <= b && A.a > A.b) return 0;
      |                         ^
answer.code:19:31: error: request for member ‘b’ in ‘A’, which is of non-class type ‘const int’
   19 |         if (a <= b && A.a > A.b) return 0;
      |                               ^
answer.code:20:24: error: request for member ‘a’ in ‘A’, which is of non-class type ‘const int’
   20 |         if (a > b && A.a > A.b) return b <= A.b;
      |                        ^
answer.code:20:30: error: request for member ‘b’ in ‘A’, which is of non-class type ‘const int’
   20 |         if (a > b && A.a > A.b) return b <= A.b;
      |                              ^
answer.code:20:47: error: request for member ‘b’ in ‘A’, which is of non-class type ‘const int’
   20 |         if (a > b && A.a > A.b) return b <= A.b;
      |                                               ^
answer.code:21:27: error: request for member ‘a’ in ‘A’, which is of non-class type ‘const int’
   21 |         else return a > A.a;
      |                           ^
In file included from /usr/include/c++/14/string:49,
                 from /usr/include/c++/14/bitset:52,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:52,
                 from answer.code:1:
/usr/include/c++/14/bits/stl_function.h: In instantiation of ‘constexpr bool std::less<_Tp>::operator()(const _Tp&, const _Tp&) const [with _Tp = node]’:
/usr/include/c++/14/bits/predefined_ops.h:196:23:   required from ‘constexpr bool __gnu_cxx::__ops::_Iter_comp_val<_Compare>::operator()(_Iterator, _Value&) [with _Iterator = __gnu_cxx::__normal_iterator<node*, std::vector<node, std::allocator<node> > >; _Value = node; _Compare = std::less<node>]’
  196 |         { return bool(_M_comp(*__it, __val)); }
      |                       ~~~~~~~^~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_heap.h:140:48:   required from ‘constexpr void std::__push_heap(_RandomAccessIterator, _Distance, _Distance, _Tp, _Compare&) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator<node*, vector<node, allocator<node> > >; _Distance = long int; _Tp = node; _Compare = __gnu_cxx::__ops::_Iter_comp_val<less<node> >]’
  140 |       while (__holeIndex > __topIndex && __comp(__first + __parent, __value))
      |                                          ~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_heap.h:216:23:   required from ‘constexpr void std::push_heap(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator<node*, vector<node, allocator<node> > >; _Compare = less<node>]’
  216 |       std::__push_heap(__first, _DistanceType((__last - __first) - 1),
      |       ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  217 |                        _DistanceType(0), _GLIBCXX_MOVE(__value), __cmp);
      |                        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_queue.h:747:16:   required from ‘void std::priority_queue<_Tp, _Sequence, _Compare>::push(value_type&&) [with _Tp = node; _Sequence = std::vector<node, std::allocator<node> >; _Compare = std::less<node>; value_type = node]’
  747 |         std::push_heap(c.begin(), c.end(), comp);
      |         ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
answer.code:63:15:   required from here
   63 |         q.push((node){x[i], y[i], i});
      |         ~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_function.h:405:20: error: no match for ‘operator<’ (operand types are ‘const node’ and ‘const node’)
  405 |       { return __x < __y; }
      |                ~~~~^~~~~
In file included from /usr/include/c++/14/bits/stl_algobase.h:64,
                 from /usr/include/c++/14/algorithm:60,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:51:
/usr/include/c++/14/bits/stl_pair.h:1023:5: note: candidate: ‘template<class _T1, class _T2, class _U1, class _U2> constexpr std::common_comparison_category_t<decltype (std::__detail::__synth3way(declval<_T1&>(), declval<_U1&>())), decltype (std::__detail::__synth3way(declval<_T2&>(), declval<_U2&>()))> std::operator<=>(const pair<_T1, _T2>&, const pair<_U1, _U2>&)’ (reversed)
 1023 |     operator<=>(const pair<_T1, _T2>& __x, const pair<_U1, _U2>& __y)
      |     ^~~~~~~~
/u...