#ifndef LOCAL
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#endif

#include <bits/stdc++.h>
using namespace std;

using ll=long long;
using uint=unsigned;

#define rng(i,a,b) for(int i=int(a);i<int(b);i++)
#define rep(i,b) rng(i,0,b)
#define pb push_back
#define eb emplace_back
#define all(x) x.begin(),x.end()
#define si(x) int(x.size())
#define a first
#define b second
#define mp make_pair
#define fr first
#define sc second
template<class t>using vc=vector<t>;
template<class t,class u>bool chmax(t&a, u b){ if(a<b){a=b;return 1;}return 0;}
template<class t,class u>bool chmin(t&a,u b){if(a>b){a=b;return 1;}return 0;}

using P=pair<int,int>;

int pre_n=-1,pre_i=-1;
void query(int n,int i){
	pre_n=n;
	pre_i=i;
	cout<<"> ";
	cout<<i+1<<endl; fflush(stdout);
}

vector<vector<int>> G;
vector<vector<pair<int,int>>> H;
vector<bool> used;
vector<int> par;
void dfs(){
	int n,m;
	cin>>n>>m; n--; G[n].resize(m,-1);
	if(pre_n!=-1){
		G[pre_n][pre_i]=n;
		rep(i,si(G[n])){
			if(G[n][i]==pre_n){
				H[n].push_back(mp(pre_n,i));
				H[pre_n].push_back(mp(n,pre_i));
			}
		}
	}
	rep(i,m){
		if(G[n][i]==-1){
			query(n,i);
			dfs();
			return;
		}
	}
	used[n]=true;
	for(auto p: H[n]){
		if(used[p.fr])continue;
		par[p.fr]=n;
		query(n,p.sc);
		dfs();
		return;
	}
	for(auto p: H[n]){
		if(p.fr==par[n]){
			query(n,p.sc);
			dfs();
			return;
		}
	}
	cout<<"!";
	rep(i,2500)rep(j,G[i].size()){
		if(G[i][j]>i)cout<<" "<<i+1<<" "<<G[i][j]+1;
	}
	cout<<endl; fflush(stdout);
	string temp; cin>>temp;
	return;
}

void solve(){
	G=vector<vector<int>>(2500);
	H=vector<vector<pair<int,int>>>(2500);
	used=vector<bool>(2500);
	par=vector<int>(2500,-1);
	pre_n=pre_i=-1;
	dfs();
}

signed main(){
	//cin.tie(0);
	//ios::sync_with_stdio(0);
	//cout<<fixed<<setprecision(20);
	
	int T; cin>>T;
	rep(t,T)solve();
}