#pragma GCC optimize(3, "unroll-loops", "no-stack-protector")
#define atsum(l, r) accumulate(l, r, 0)
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/hash_policy.hpp>
using namespace std;
using ll = long long;
using ull = unsigned long long;
constexpr int inf = 0x3f3f3f3f;
constexpr ll INF = 0x3f3f3f3f3f3f3f3f;
template <typename T>
inline void chkmin(T &x, T y) { x = min(x, y); }
template <typename T>
inline void chkmax(T &x, T y) { x = max(x, y); }
namespace FastIO
{
// ------------------------------
#define IN_HAS_NEG
#define OUT_HAS_NEG
#define CHK_EOF
#define DISABLE_MMAP
// ------------------------------
#if __cplusplus < 201400
#error Please use C++14 or higher.
#endif
#if __cplusplus > 201700
#define INLINE_V inline
#else
#define INLINE_V
#endif
#if ( defined(LOCAL) || defined (_WIN32) ) && !defined(DISABLE_MMAP)
#define DISABLE_MMAP
#endif
#ifndef DISABLE_MMAP
#include<sys/mman.h>
#endif
#ifdef LOCAL
    inline char gc() { return getchar(); }
    inline void pc(char c) { putchar(c); }
#else
#ifdef DISABLE_MMAP
    INLINE_V constexpr int _READ_SIZE = 1 << 18;
    INLINE_V static char _read_buffer[_READ_SIZE], *_read_ptr = nullptr, *_read_ptr_end = nullptr;
    inline char gc()
    {
        if ( __builtin_expect(_read_ptr == _read_ptr_end, false) )
        {
            _read_ptr = _read_buffer;
            _read_ptr_end = _read_buffer + fread(_read_buffer, 1, _READ_SIZE, stdin);
#ifdef CHK_EOF
            if ( __builtin_expect(_read_ptr == _read_ptr_end, false) ) return EOF;
#endif
        }
        return *_read_ptr++;
    }
#else
    INLINE_V static const char *_read_ptr = (const char *)mmap(nullptr, INT_MAX, 1, 2, 0, 0);
    inline char gc() { return *_read_ptr++; }
#endif
    INLINE_V constexpr int _WRITE_SIZE = 1 << 18;
    INLINE_V static char _write_buffer[_WRITE_SIZE], *_write_ptr = _write_buffer;
    inline void pc(char c)
    {
        *_write_ptr++ = c;
        if ( __builtin_expect(_write_buffer + _WRITE_SIZE == _write_ptr, false) )
        {
            fwrite(_write_buffer, 1, _write_ptr - _write_buffer, stdout);
            _write_ptr = _write_buffer;
        }
    }
    INLINE_V struct _auto_flush
    {
        ~_auto_flush() { fwrite(_write_buffer, 1, _write_ptr - _write_buffer, stdout); }
    }	_auto_flush;
#endif
#ifdef CHK_EOF
    inline bool _isdigit(char c) { return ( c & 16 ) && c != EOF; }
    inline bool _isgraph(char c) { return c > 32 && c != EOF; }
#else
    inline bool _isdigit(char c) { return c & 16; }
    inline bool _isgraph(char c) { return c > 32; }
#endif
    template < class T >
    INLINE_V constexpr bool _is_integer = numeric_limits < T >::is_integer;
    template < class T >
    INLINE_V constexpr bool _is_signed = numeric_limits < T >::is_signed;
    template < class T >
    INLINE_V constexpr bool _is_unsigned = _is_integer < T > && !_is_signed < T >;
    template <> INLINE_V constexpr bool _is_integer < __int128 > = true;
    template <> INLINE_V constexpr bool _is_integer < __uint128_t > = true;
    template <> INLINE_V constexpr bool _is_signed < __int128 > = true;
    template <> INLINE_V constexpr bool _is_unsigned < __uint128_t > = true;
#undef INLINE_V
    inline void read(char &c) { do c = gc(); while ( !_isgraph(c) ); }
    inline void read_cstr(char *s)
    {
        char c = gc(); while ( !_isgraph(c) ) c = gc();
        while ( _isgraph(c) ) *s++ = c, c = gc();
        *s = 0;
    }
    inline void read(string &s)
    {
        char c = gc(); s.clear(); while ( !_isgraph(c) ) c = gc();
        while ( _isgraph(c) ) s.push_back(c), c = gc();
    }
#ifdef IN_HAS_NEG
    template < class T, enable_if_t < _is_signed < T >, int > = 0 >
    inline void read(T &x)
    {
        char c = gc(); bool f = true; x = 0;
        while ( !_isdigit(c) ) { if ( c == 45 ) f = false; c = gc(); }
        if ( f ) while ( _isdigit(c) ) x = x * 10 + ( c & 15 ), c = gc();
        else     while ( _isdigit(c) ) x = x * 10 - ( c & 15 ), c = gc();
    }
    template < class T, enable_if_t < _is_unsigned < T >, int > = 0 >
#else
    template < class T, enable_if_t < _is_integer < T >, int > = 0 >
#endif
    inline void read(T &x)
    {
        char c = gc(); while ( !_isdigit(c) ) c = gc();
        x = 0; while ( _isdigit(c) ) x = x * 10 + ( c & 15 ), c = gc();
    }
    inline void write(char c) { pc(c); }
    inline void write_cstr(const char *s) { while ( *s ) pc(*s++); }
    inline void write(const string &s) { for ( char c : s ) pc(c); }
#ifdef OUT_HAS_NEG
    template < class T, enable_if_t < _is_signed < T >, int > = 0 >
    inline void write(T x)
    {
        char buffer[numeric_limits < T >::digits10 + 1]; int digits = 0;
        if ( x >= 0 )  do buffer[digits++] =  ( x % 10 ) | 48, x /= 10; while ( x );
        else { pc(45); do buffer[digits++] = -( x % 10 ) | 48, x /= 10; while ( x ); }
        while ( digits ) pc(buffer[--digits]);
    }
    template < class T, enable_if_t < _is_unsigned < T >, int > = 0 >
#else
    template < class T, enable_if_t < _is_integer < T >, int > = 0 >
#endif
    inline void write(T x)
    {
        char buffer[numeric_limits < T >::digits10 + 1]; int digits = 0;
        do buffer[digits++] = ( x % 10 ) | 48, x /= 10; while ( x );
        while ( digits ) pc(buffer[--digits]);
    }
    template < int N > struct _tuple_io_helper
    {
        template < class ...T >
        static inline void _read(tuple < T... > &x)
        { _tuple_io_helper < N - 1 >::_read(x), read(get < N - 1 > (x)); }
        template < class ...T >
        static inline void _write(const tuple < T... > &x)
        { _tuple_io_helper < N - 1 >::_write(x), pc(32), write(get < N - 1 > (x)); }
    };
    template <> struct _tuple_io_helper < 1 >
    {
        template < class ...T >
        static inline void _read(tuple < T... > &x) { read(get < 0 > (x)); }
        template < class ...T >
        static inline void _write(const tuple < T... > &x) { write(get < 0 > (x)); }
    };
    template < class ...T >
    inline void read(tuple < T... > &x) { _tuple_io_helper < sizeof...(T) >::_read(x); }
    template < class ...T >
    inline void write(const tuple < T... > &x) { _tuple_io_helper < sizeof...(T) >::_write(x); }
    template < class T1, class T2 >
    inline void read(pair < T1, T2 > &x) { read(x.first), read(x.second); }
    template < class T1, class T2 >
    inline void write(const pair < T1, T2 > &x) { write(x.first), pc(32), write(x.second); }
    template < class T1, class ...T2 >
    inline void read(T1 &x, T2 &...y) { read(x), read(y...); }
    template < class ...T >
    inline void read_cstr(char *x, T *...y) { read_cstr(x), read_cstr(y...); }
    template < class T1, class ...T2 >
    inline void write(const T1 &x, const T2 &...y) { write(x), write(y...); }
    template < class ...T >
    inline void write_cstr(const char *x, const T *...y) { write_cstr(x), write_cstr(y...); }
    template < class T >
    inline void print(const T &x) { write(x); }
    inline void print_cstr(const char *x) { write_cstr(x); }
    template < class T1, class ...T2 >
    inline void print(const T1 &x, const T2 &...y) { print(x), pc(32), print(y...); }
    template < class ...T >
    inline void print_cstr(const char *x, const T *...y) { print_cstr(x), pc(32), print_cstr(y...); }
    inline void println() { pc(10); }
    inline void println_cstr() { pc(10); }
    template < class ...T >
    inline void println(const T &...x) { print(x...), pc(10); }
    template < class ...T >
    inline void println_cstr(const T *...x) { print_cstr(x...), pc(10); }
}
using namespace FastIO;
template <typename T>
inline void clear(T &x) {
    T y;
    swap(x, y);
}
const int N = 2e5 + 10;
struct Seg {
    unsigned w[N << 2], len[N << 2], tag[N << 2];
    bitset<N << 2> used;
    int st[N << 2], top;
    inline void maketag(int u, unsigned v) {
        if (!used.test(u)) used.set(u), st[++top] = u;
        w[u] += len[u] * v, tag[u] += v;
    }
    inline void pushdown(int u) {
        if (tag[u]) maketag(u << 1, tag[u]), maketag(u << 1 | 1, tag[u]), tag[u] = 0;
    } 
    inline void update(int u, int L, int R, int l, int r, unsigned v) {
        if (!used.test(u)) used.set(u), st[++top] = u;
        if (L >= l && R <= r) return maketag(u, v);
        if (L > r || R < l) return;
        int M = L + R >> 1;
        pushdown(u);
        update(u << 1, L, M, l, r, v), update(u << 1 | 1, M + 1, R, l, r, v);
        w[u] = w[u << 1] + w[u << 1 | 1];
        len[u] = len[u << 1] + len[u << 1 | 1];
    }
    inline void ins(int u, int L, int R, int x, unsigned v) {
        if (!used.test(u)) used.set(u), st[++top] = u;
        if (L == R) return len[u] += v, void(w[u] += tag[u] * v);
        pushdown(u);
        int M = L + R >> 1;
        if (x <= M )ins(u << 1, L, M, x, v);
        else  ins(u << 1 | 1, M + 1, R, x, v);
        w[u] = w[u << 1] + w[u << 1 | 1];
        len[u] = len[u << 1] + len[u << 1 | 1];
    }
    inline unsigned query(int u, int L, int R, int l, int r) {
        if (!used.test(u)) used.set(u), st[++top] = u;
        if (L >= l && R <= r) return w[u];
        if (L > r || R < l) return 0;
        pushdown(u);
        int M = L + R >> 1;
        return query(u << 1, L, M, l, r) + query(u << 1 | 1, M + 1, R, l, r);
    }
    inline void clr() {
        while (top) w[st[top]] = tag[st[top]] = len[st[top]] = 0, used.reset(st[top--]);
    }
} seg;
struct Tree{
    basic_string<int> vec[N];
    int top[N], son[N], siz[N], dfn[N], dfncnt, fa[N], dep[N];
    void dfs(int u) {
        siz[u] = 1;
        for (int v : vec[u])
            if (v != fa[u]) {
                fa[v] = u, dep[v] = dep[u] + 1, dfs(v), siz[u] += siz[v];
                if (siz[v] > siz[son[u]]) son[u] = v;
            }
    }
    void dfs2(int u) {
        dfn[u] = ++dfncnt;
        if (son[u]) top[son[u]] = top[u], dfs2(son[u]);
        for (int v : vec[u])
            if (v != fa[u] && v != son[u]) dfs2(top[v] = v);
    }
    inline int lca(int u, int v) {
        while (top[u] != top[v]) dep[top[u]] > dep[top[v]] ? u = fa[top[u]] : v = fa[top[v]];
        return dep[u] < dep[v] ? u : v; 
    }
    inline int dist(int u, int v) { return dep[u] + dep[v] - 2 * dep[lca(u, v)]; }
    inline void addedge(int u, int v) {
        vec[u] += v;
        vec[v] += u;
    }
} mn, mx;
int fa[N], n;
bitset<N> qwq;
void dfsa(int u) {
    qwq.set(u);
    for (int v : mn.vec[u])
        if (v != mn.fa[u]) dfsa(v);
}
int dfsb(int u) {
    int ans = qwq.test(u);
    for (int v : mx.vec[u])
        if (v != mx.fa[u]) ans += dfsb(v);
    return ans;
}
basic_string<int> G[N];
inline int find(int u) { return fa[u] == u ? u : (fa[u] = find(fa[u])); }
int T;
unsigned ans;
inline void update(int u) {
    seg.ins(1, 1, n, mx.dfn[u], u);
    int c = u;
    while (c) {
        seg.update(1, 1, n, mx.dfn[mx.top[c]], mx.dfn[c], 1);
        c = mx.fa[mx.top[c]];
    }
}
inline void ins(int u) {
    update(u);
    for (int v : mn.vec[u])
        if (v != mn.fa[u]) ins(v);
}
inline unsigned query(int u) {
    unsigned ans = 0;
    while (u) ans += seg.query(1, 1, n, mx.dfn[mx.top[u]], mx.dfn[u]), u = mx.fa[mx.top[u]];
    return ans;
}
inline void dsu(int u) {
    for (int v : mn.vec[u])
        if (v != mn.fa[u] && v != mn.son[u]) dsu(v), seg.clr();
    if (mn.son[u]) dsu(mn.son[u]);
    update(u);
    for (int v : mn.vec[u])
        if (v != mn.fa[u] && v != mn.son[u]) ins(v);
    ans += u * query(u);
}
inline void work() {
    ans = 0;
    for (int i = 1; i <= n; i++) mn.son[i] = mx.son[i] = 0, clear(mx.vec[i]), clear(mn.vec[i]);
    for (int i = 1; i <= n; i++) mn.fa[i] = mx.fa[i] = 0;
    mn.dfncnt = mx.dfncnt = 0;
    read(n);
    for (int i = 1; i <= n; i++) clear(G[i]);
    for (int i = 1; i < n; i++) {
        int u, v;
        read(u, v);
        G[u] += v, G[v] += u;
    }
    for (int i = 1; i <= n; i++) fa[i] = i;
    for (int i = 1; i <= n; i++)
        for (int v : G[i])
            if (v < i) mx.addedge(find(v), i), fa[find(v)] = i;
    for (int i = 1; i <= n; i++) fa[i] = i;
    for (int i = n; i; i--)
        for (int v : G[i])
            if (v > i) mn.addedge(find(v), i), fa[find(v)] = i;
    mn.dfs(1), mx.dfs(n);
    mn.dfs2(mn.top[1] = 1), mx.dfs2(mx.top[n] = n);
    seg.clr();
    dsu(1);
    println(ans);
}
int main() {
freopen("delete.in","r",stdin);
freopen("delete.out","w",stdout);
    read(T);
    while (T--) work();
    return 0;
}





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