#include <bits/stdc++.h>
#define IOS1 std::ios::sync_with_stdio(false)
#define IOS2 std::cin.tie(nullptr)
#define mode1 1
#define mode2 1

using i64 = long long;
using ui64 = unsigned long long;

constexpr i64 INF = 0x3f3f3f3f3f3f3f3f;
constexpr int inf = 1e9;
constexpr int mod = 1e9 + 7;

template<class T1, class T2> std::istream& operator>>(std::istream& cin, std::pair<T1, T2>& a) { return cin >> a.first >> a.second; };
template<class T1, class T2> std::ostream& operator<<(std::ostream& cout, std::pair<T1, T2>& a) { return cout << a.first << ' ' << a.second; };
template<class T> std::ostream& operator<<(std::ostream& cout, std::vector<T>& a)
{
    for (int i = 0; i < a.size(); ++i)
        cout << a[i] << " \n"[i == a.size() - 1];
    return cout;
}

inline int read()
{
    int x = 0, f = 1;
    char ch = getchar();
    while (ch < '0' || ch>'9')
    {
        if (ch == '-')
            f = -1;
        ch = getchar();
    }
    while (ch >= '0' && ch <= '9')
        x = x * 10 + ch - '0', ch = getchar();
    return x * f;
}

inline void write(int x)
{
    if (x < 0)
        putchar('-'), x = -x;
    if (x > 9)
        write(x / 10);
    putchar(x % 10 + '0');
    return;
}

class Solution
{
public:
    void solve()
    {
        int n;
        std::cin >> n;
        std::vector<std::vector<int>> adj(n + 1);
        for (int i = 0; i < n; ++i)
        {
            int l, r;
            std::cin >> l >> r;
            ++r;
            if (r > n) r = 1;
            adj[l].emplace_back(r);
            adj[r].emplace_back(l);
        }
        std::vector<bool> vis(n + 1);
        int cnt = 0;
        std::function<void(int, int)> dfs = [&](int v, int f) -> void
        {
            ++cnt;
            vis[v] = 1;
            for (int x : adj[v])
            {
                if (x == f) continue;
                if (!vis[x]) dfs(x, v);
            }
        };
        dfs(1, 0);
        std::cout << (cnt == n) << "\n";
    }
};

int main()
{
    IOS1;
    IOS2;

#if mode1
    int t;
    std::cin >> t;
    while (t--)
    {
        Solution().solve();
    }
#elif mode2
    Solution().solve();
#endif

    return 0;
}