#include<bits/stdc++.h>
#define int long long
#define ll long long
using namespace std;
const ll maxn=2505,maxm=1e4+5;
ll tot,s[maxn];
pair<ll,ll>gt(ll x){
	ll res=0,siz=0;
	cout<<"> "<<x<<endl;
	cin>>res>>siz;
	s[res]=siz;
	return make_pair(res,siz);
	tot++;
}
ll e[maxn][maxn];
vector<ll>lst[maxn];
ll cur[maxn];
void dfs(ll x,ll siz,ll fa){
	if(e[x][fa]){
//		cout<<"from "<<x<<" back "<<fa<<endl;
		gt(e[x][fa]);
		return ;
	}
//	cout<<"now "<<x<<" "<<cur[x]<<endl;
	while(cur[x]<=siz){
		pair<ll,ll>res=gt(cur[x]);
//		cout<<"now "<<x<<" "<<res.first<<endl;
		e[x][res.first]=cur[x];
		lst[x].push_back(res.first);
		cur[x]++;
		dfs(res.first,res.second,x);
	}
	if(e[x][fa]&&cur[fa]<=s[fa])gt(e[x][fa]);
	return ;
}
string c;
void solve()
{
	tot=0;
	for(ll i=1;i<=2500;i++){
		cur[i]=1;
		s[i]=0;
		for(auto it:lst[i])e[i][it]=0;
		lst[i].clear();
	}
	ll x=0,siz=0;
	cin>>x>>siz;
	dfs(x,siz,0);
	cout<<"! ";
	for(ll i=1;i<=2500;i++){
		if(lst[i].empty())continue;
		for(auto it:lst[i]){
			if(i<it)cout<<i<<" "<<it<<" ";
		}
	}
	cin>>c;
//	cout<<endl;
//	for(ll i=1;i<=4;i++)cout<<cur[i]<<endl;
//	cout<<tot<<endl;
	cout<<endl;
	return ;
}

signed main()
{
	int T;
	cin>>T;
	while(T--)
		solve();
}