#include <bits/stdc++.h>
using namespace std;
typedef pair<int,int> pii;
typedef long long ll;
typedef ll i64;
typedef __int128 i128;
constexpr int maxn=5e5+9;
char fuck[200];
namespace Online {
    pair<int,int> go(int di)
    {
        static int tmp,tmp2;
        printf("> %d\n",di);
        fflush(stdout);
        scanf("%d %d",&tmp,&tmp2);
        return {tmp,tmp2};
    }
    bool answer(const vector<pii> &ans)
    {
        printf("!");
        for(auto[u,v]:ans) printf(" %d %d",u,v);
        puts("");
        fflush(stdout);
        scanf("%s",fuck);
        fflush(stdout);
        return !strcmp(fuck,"Correct");
    }
    pair<int,int> init()
    {
        static int tmp,tmp2;
        fflush(stdout);
        scanf("%d %d",&tmp,&tmp2);
        return {tmp,tmp2};
    }
}


mt19937 rng{random_device{}()};
namespace Tester {
    vector<int> e[maxn],Etest[maxn];
    int n,now,m;
    int cnt=0;
    pair<int,int> init()
    {
        n=100; cnt=0;
        now=2;
        n=4;
        e[1].push_back(2);
        e[1].push_back(3);
        e[1].push_back(4);
        e[2].push_back(4);
        e[2].push_back(1);
        e[3].push_back(1);
        e[4].push_back(1);
        e[4].push_back(2);
        return {now,e[now].size()};
    }
    pair<int,int> go(int di)
    {
        if(di<=0 || di>e[now].size())
        {
            printf("%d %d %d\n",now,di,e[now].size());
            exit(-1);
        }
        now=e[now][di-1];
        return {now,e[now].size()};
    }
    bool answer(const vector<pii> &ans)
    {
        for(int i=1;i<=n;++i) Etest[i].clear();
        for(auto[l,r]:ans) Etest[l].push_back(r),
            Etest[r].push_back(l);
        for(int i=1;i<=n;++i)
        {
            sort(Etest[i].begin(),Etest[i].end());
            sort(e[i].begin(),e[i].end());
            if(Etest[i]!=e[i]) return false;
        }
        return true;
    }
}
// using namespace Tester;
using namespace Online;
int deg[2509],from[2509];
int findpos(int v,const vector<int> &u,int U=0)
{
    for(int i=0;i<u.size();++i)
        if(u[i]==v) return i+1;
    // printf("%d %d failed\n",v,U);
    return -1;
}
int gg=0;
void solve()
{
    vector<int> e[2509];
    vector<pii> ans;
    int N; N=0;
    auto[cur,degcur]=init();
    int rt=N=cur;
    memset(deg,0,sizeof(deg));
    deg[cur]=degcur;
    memset(from,0,sizeof(from));
    // printf("SOLVING %d\n",++gg);
    from[cur]=-1;
    for(;;)
    {
        int lastnode=cur;
        // printf("now at %d\n",cur);
        if(e[cur].size()==deg[cur])
        {
            // 走完了
            // printf("its ending and go to from\n");
            if(cur==rt) break;
            auto[nxt,nxtdeg]=go(findpos(from[cur],e[cur],cur));
            deg[cur=nxt]=nxtdeg;
        }
        else
        {
            // get nxt road
            // printf("go through edge #%d\n",e[cur].size()+1);
            auto[nxt,nxtdeg]=go(e[cur].size()+1);
            // printf("its %d\n",nxt);
            e[cur].push_back(nxt); deg[nxt]=nxtdeg;
            N=max(N,nxt);
            cur=nxt;
            if(!from[nxt])
                from[nxt]=lastnode;//,printf("first visit.\n");
            else if(nxt==from[lastnode])
            {
               //printf("its from nnode (%d), and will back\n",from[lastnode]);
                auto[nxt2,tmp]=go(findpos(lastnode,e[nxt],nxt));
                // assert(nxt2==lastnode);
                deg[cur=nxt2]=tmp;
            }
        }
    }
    for(int i=1;i<=N;++i)
        for(int j:e[i])
            if(j>i) ans.push_back({i,j});
    if(!answer(ans)) puts("failed"),exit(-2);
    //else fprintf(stderr,"NIUBI\n");
}
int main()
{
    int t;
    scanf("%d",&t);
    while(t--) solve();
    return 0;
}