#include<bits/stdc++.h>

#define ll long long
#define mk make_pair
#define fi first
#define se second

using namespace std;

inline int read(){
	int x=0,f=1;char c=getchar();
	for(;(c<'0'||c>'9');c=getchar()){if(c=='-')f=-1;}
	for(;(c>='0'&&c<='9');c=getchar())x=x*10+(c&15);
	return x*f;
}

const int mod=998244353;
int ksm(int x,int y,int p=mod){
	int ans=1;
	for(int i=y;i;i>>=1,x=1ll*x*x%p)if(i&1)ans=1ll*ans*x%p;
	return ans%p;
}
int inv(int x,int p=mod){return ksm(x,p-2,p)%p;}
mt19937 rnd(time(0));
int randint(int l,int r){return rnd()%(r-l+1)+l;}
void add(int &x,int v){x+=v;if(x>=mod)x-=mod;}
void Mod(int &x){if(x>=mod)x-=mod;}
int cmod(int x){if(x>=mod)x-=mod;return x;}

void cmax(int &x,int v){x=max(x,v);}
void cmin(int &x,int v){x=min(x,v);}

const int N=2505;
vector<int>G[N];
set<int>adj[N];
int deg[N],pre[N];
bool vis[N];
void solve(){
	int u=read();deg[u]=read();
	vector<pair<int,int> >edges;
	set<int>nodes;
	if(deg[u]==0)return cout<<"!"<<endl,void();
	vector<int>cur;
	auto clr=[&](){
		// cout<<"clear : cur = ";for(int x:cur)cout<<x<<" ";puts("");
		for(int x:cur)vis[x]=0;
		cur.clear();
	};
	auto bfs=[&](int u){
		queue<int>q;q.push(u),vis[u]=1,cur.emplace_back(u);
		// cout<<"bfs "<<u<<endl;
		// cout<<"now nodes = :\n";
		// for(int x:nodes){
		// 	cout<<"x = "<<x<<" G = ";for(int y:G[x])cout<<y<<" ";puts("");
		// }
		while(q.size()){
			int x=q.front();q.pop();
			// cout<<"x = "<<x<<endl;
			if(deg[x]>G[x].size()){clr();return x;}
			for(int y:G[x])if(!vis[y]){
				// cout<<" -> "<<y<<endl;
				pre[y]=x,q.push(y),vis[y]=1,cur.emplace_back(y);
			}
		}
		clr();
		return -1;
	};
	auto gogo=[&](int u,int x){
		vector<int>nodes;
		// cout<<"gogo "<<u<<" -> "<<x<<endl;
		while(x!=u)nodes.emplace_back(x),x=pre[x];
		reverse(nodes.begin(),nodes.end());
		for(int i=0;i<nodes.size();i++){
			for(int j=0;j<G[u].size();j++){
				if(G[u][j]==nodes[i]){
					cout<<"> "<<j+1<<endl;
					break;
				}
			}
			u=read(),deg[u]=read();assert(u==nodes[i]);
		}
	};
	auto chk=[&](int u){
		// cout<<"chk "<<u<<" |G| = "<<G[u].size()<<" deg = "<<deg[u]<<endl;
		if(G[u].size()==deg[u]-1){
			for(int v:adj[u]){
				bool chk=0;
				for(int k:G[u])if(v==k)chk=1;
				if(chk)continue;
				// cout<<"succeeded : v = "<<v<<endl;
				G[u].emplace_back(v);return ;
			}
		}
		// puts("failed.");
	};
	while(1){
		nodes.insert(u);
		// cout<<"now u = "<<u<<endl;
		int v=bfs(u);
		if(v==-1)break;
		gogo(u,v);u=v;
		
		int id=G[u].size()+1;
		cout<<"> "<<id<<endl;
		int p=read();deg[p]=read();
		G[u].emplace_back(p);
		adj[u].insert(p),adj[p].insert(u),chk(u),chk(p);
		u=p;
	}
	vector<pair<int,int> >ans;
	for(int x:nodes)for(int y:G[x])if(y>x)ans.emplace_back(mk(x,y));
	cout<<"! ";for(auto [u,v]:ans)cout<<u<<" "<<v<<" ";cout<<endl;

	int n=*--nodes.end();
	for(int i=1;i<=n;i++)adj[i].clear(),G[i].clear(),deg[i]=0,pre[i]=0;
}

signed main(void){

	int tt=read();while(tt--)solve();

	return 0;
}