#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using db = double;
constexpr int mod = 998244353;

constexpr int N = 2510;
int n, deg[N];
vector<int> edge[N];
int move(int id) {
    cout << "> " << id << endl;
    int x; cin >> x >> deg[x];
    return x;
}
int cur[N], vis[N], fa[N], adj[N][N];
void dfs(int u) {
    if (!vis[u]) ++n;
    vis[u] = true;
    for (int &i = cur[u]; i < deg[u];) {
        int v = move(++i);
        edge[u].push_back(v);
        adj[u][v] = i;
        if (v > 1 && fa[v] == 0) fa[v] = u;
        if (v == fa[u]) {
            move(adj[v][u]);
        } else {
            dfs(v);
        }
    }
    if (adj[u][fa[u]]) move(adj[u][fa[u]]);
}
void solve() {
    int root; cin >> root >> deg[1];
    dfs(1);
    cout << "!";
    for (int i = 1; i <= n; i++) {
        for (auto j : edge[i]) {
            if (i < j) cout << ' ' << i << ' ' << j;
        }
    }
    cout << endl;
    string Correct; cin >> Correct;
    for (int i = 1; i <= n; i++) {
        deg[i] = cur[i] = vis[i] = fa[i] = 0;
        for (auto j : edge[i]) adj[i][j] = 0;
        edge[i].clear();
    }
    n = 0;
}
int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int tt = 1;
    cin >> tt;
    while (tt--) {
        solve();
    }
    return 0;
}