//
// Created by codicon on 2/17/2024 at 10:40 AM.
//

#include <bits/stdc++.h>

using namespace std;

mt19937_64 rng(97389987);

const int MAXN = 3e3;

bool vis[MAXN];
vector<int> edges_left[MAXN];
int par[MAXN];
map<int, int> adj[MAXN];

set<pair<int, int>> edges;

pair<int, int> move(int i) {
    cout << "> " << i << endl;
    int x, deg; cin >> x >> deg;
    return {x, deg};
}

int main() {
    int t; cin >> t;

    while (t--) {
        memset(vis, 0, sizeof(vis));
        edges.clear();

        int p=0, last_edge_i=0, x, deg; // State
        cin >> x >> deg;
        while (true) {
            if (not vis[x]) {
                vis[x] = true;

                // Add parent
                par[x] = p;
                adj[p][x] = last_edge_i;

                for (auto i: views::iota(1, deg+1)) {
                    edges_left[x].push_back(i);
                }
                shuffle(edges_left[x].begin(), edges_left[x].end(), rng); // Just in case?
            }

            if (not empty(edges_left[x])) {
                int edge_i = edges_left[x].back();
                edges_left[x].pop_back();

                auto [nx, ndeg] = move(edge_i);

                if (nx == par[x]) {
                    // Moved to parent, so move back

                    adj[x][par[x]] = edge_i; // Add so we can move back to parent later

                    // Ensures cycles are only of the form "go up then go down"?
                    move(adj[par[x]][x]);
                }
                else {
                    // Trying edge out
                    edges.insert({min(x, nx), max(x, nx)});

                    last_edge_i = edge_i;
                    p = x;
                    x = nx;
                    deg = ndeg;
                }
            }
            else {
                // Finished searching this subtree
                // Move back to parent

                if (x == 1) {
                    break;
                }

                auto [nx, ndeg] = move(adj[x][par[x]]);
                x = nx;
                deg = ndeg;
            }
        }

        cout << "!";
        for (auto [x, y]: edges) {
            cout << ' ' << x << ' ' << y;
        }
        cout << endl;

        string a; cin >> a;
        if (a == "Wrong") {
            return 0;
        }
    }
}