#include <bits/stdc++.h>
#define IOS ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define i64 long long
#define int long long
#define endl '\n'
#define lb(x) ((x) & (-x))
using namespace std;
const i64 mod = 1e9+7;
const int maxn = 1e4+10;

signed main()
{
    IOS;
    int t; cin >> t;
    while(t--)
    {
        int n; cin >> n;
        vector<int> a(n+1);
        vector<vector<int>> cnt(n+1,vector<int>(n+1));
        for(int i = 1; i <= n; ++i)
        {
            for(int j = 1; j <= n; ++j) cin >> a[j];
            for(int j = 2; j <= n; ++j)
            {
                for(int k = 1; k < j; ++k)
                {
                    int x = a[j],y = a[k];
                    if(x > y) swap(x,y);
                    cnt[x][y] += n-j+2;
                }
            }
        }
        struct node{int x,y,z; };
        vector<node> v;
        for(int i = 1; i <= n; ++i)
        {
            for(int j = i+1; j <= n; ++j) v.push_back({i,j,cnt[i][j]});
        }
        sort(v.begin(),v.end(),[&](node a,node b) { return a.z > b.z; });
        vector<int> f(n+1);
        for(int i = 1; i <= n; ++i) f[i] = i;
        auto get = [&](auto self,int x) -> int
        {
            if(f[x] == x) return x;
            return f[x] = self(self,f[x]);
        };
        vector<pair<int,int>> ans;
        for(node &a : v)
        {
            int x = get(get,a.x),y = get(get,a.y);
            if(x != y)
            {
                ans.push_back({a.x,a.y});
                f[x] = y;
            }
        }
        for(auto &[x,y] : ans) cout << x << ' ' << y << endl;
    }
    return 0;
}