#include <bits/stdc++.h>

using namespace std;
using ll = long long;
constexpr int N = 2505;


pair<int, int> ask(int id) {
    cout << "> " << id + 1 << endl;
    int to, d;
    cin >> to >> d;
    --to;
    return {to, d};
}

void solve() {
    int v, d;
    cin >> v >> d;
    --v;
    vector<int> deg(N, -1);
    vector<int> ptr(N, 0);
    vector<map<int, int>> where(N);
    deg[v] = d;
    vector<pair<int, int>> res;
    vector<vector<int>> g(N);
    while (1) {
        if (deg[v] == ptr[v]) {
            vector<int> pred(N, -1);
            vector<char> used(N, 0);
            queue<int> q;
            q.push(v);
            used[v] = 1;
            int re = -1;
            int st =v;
            while (q.size() && !~re) {
                int v = q.front();
                q.pop();
                for (auto to: g[v]) {
                    if (!used[to]) {
                        used[to] = 1;
                        q.push(to);
                        pred[to] = v;
                        if (ptr[to] < deg[to]) {
                            for (int cur = to;; cur = pred[cur]) {
                                if (pred[cur] == st) {
                                    re = cur;
                                    break;
                                }
                            }
                            break;
                        }
                    }
                }
            }
            if(!~re)break;
            ask(where[v][re]);
            v = re;
            continue;
        }
        auto [to, d] = ask(ptr[v]);
        where[v][to] = ptr[v];
        g[v].push_back(to);
        res.push_back({min(v, to), max(v, to)});
        ++ptr[v];
        deg[to] = d;
        v = to;
    }
    sort(res.begin(), res.end());
    res.resize(unique(res.begin(), res.end()) - res.begin());
    cout << "! ";
    for (auto [x, y]: res) {
        cout << x + 1 << " " << y + 1 << " ";
    }
    cout << endl;
    string c;
    cin >> c;
    if (c == "Wrong") {
        exit(0);
    }
}

int main() {
    cin.tie(0)->sync_with_stdio(false);
    ll t;
    cin >> t;
    while (t--)solve();
    return 0;
}