#include<bits/stdc++.h>
using namespace std;
template <typename T> inline void read(T &x)
{
	x=0;T f=1;char c=getchar();
	for(;!isdigit(c);c=getchar()) if(c=='-')f=-1;
	for(;isdigit(c);c=getchar()) x=(x<<1)+(x<<3)+(c^48);
	x*=f;
}
template <typename T,typename ...Args>void read(T &x,Args&...args){read(x),read(args...);}
template <typename T> void print(T x)
{
	if(x<0) x=-x,putchar('-');
	if(x>9) print(x/10);
	putchar(x%10+48);
}
template <typename T> void print(T x,char c){print(x); putchar(c);}
template<typename T>inline void output(T x){print(x,' ');}
template<typename T,typename ...Arg>inline void output(T x,Arg ...arg){output(x);output(arg...);}
const int N=2507;
int T,n,d[N],v[N];
vector<int>E[N];
map<pair<int,int>,int>RE;
int inter(int id)
{
	cout<<"> "<<id<<endl; cout.flush();
	int x; read(x); read(d[x]);
	return n=max(n,x),x;
}
void dfs(int x)
{
	int siz=E[x].size();
	if(siz<d[x])
	{
		int y=inter(siz+1);
		E[x].push_back(y);
		RE[{x,y}]=siz+1; dfs(y);
	}
	else
	{
		v[x]=1;
		for(int i=0;i<siz;i++)
		{
			int y=E[x][i];
			if(v[y]) continue;
			inter(i+1); dfs(y);
			inter(RE[{y,x}]);
		}
	}
}
void solve()
{
	read(n); read(d[n]); dfs(n);
	cout<<"! "; char str[10]; RE.clear();
	for(int i=1;i<=n;i++) for(auto j:E[i])
		if(i<j) cout<<i<<" "<<j<<" ";
	cout<<endl; cout.flush(); scanf("%s",str);
	for(int i=1;i<=n;i++) E[i].clear(),v[i]=d[i]=0;
}
int main()
{
	read(T);
	while(T--) solve();
	return 0;
}