#include <bits/stdc++.h>
using namespace std;
#define int long long
#define inf 0x3f3f3f3f3f3f3f3fll
#define For(i,l,r) for(int i=(l);i<=(r);++i)
#define Rof(i,l,r) for(int i=(l);i>=(r);--i)
bool M_S;
const int N=2505;
int n=2500,s,deg[N],uid[N][N];
vector<int> e[N];
int walk(int x){
	cout<<"> "<<x<<"\n";cout.flush();
	int u;cin>>u;cin>>deg[u];return u;
}
bool vis[N];
void dfs(int u){
	if(e[u].size()<deg[u]){
		int i=e[u].size()+1,v=walk(i);
		uid[u][v]=i,e[u].push_back(v);
		dfs(v);return ;
	}
	vis[u]=1;
	For(i,1,(int)e[u].size()){
		int v=e[u][i-1];if(vis[v]) continue;
		walk(i);dfs(v);walk(uid[v][u]);
	}
}
void MAIN1(){
	cin>>s;cin>>deg[s];
	dfs(s);
	cout<<"! ";For(u,1,n) for(int v:e[u]) if(u<v) cout<<u<<" "<<v<<" ";cout<<"\n",cout.flush();
	string Correct;cin>>Correct;
}
void _MAIN1(){
	For(u,1,n) e[u].clear(),vis[u]=0;
}
int T;
void MAIN(){
	cin>>T;
	For(_,1,T) MAIN1(),_MAIN1();
}
bool M_T;
signed main(){
	// freopen(".in","r",stdin);
	// freopen(".out","w",stdout);
	ios::sync_with_stdio(false);
	cin.tie(0),cout.tie(0);
	double T_S=clock();MAIN();double T_T=clock();
	cerr<<"T:"<<(T_T-T_S)/CLOCKS_PER_SEC<<"s ";
	cerr<<"M:"<<(&M_S-&M_T)/1048576<<"MiB\n";
	return 0;
}