#pragma GCC optimize(3)
#include <bits/stdc++.h>
#define ll long long
#define pii pair<int,int>
#define N 100005
#define MOD 998244353
using namespace std;
int q(int u,int v)
{
    cout<<"? "<<u<<' '<<v<<'\n';
    cout.flush();
    int res; cin>>res;
    return res;
}
int n;
int x[N],y[N];
bitset<N> tag;
int siz[N], fa[N];
int rt;
pii p1,p2;
void dfs1(int u)
{
    siz[u] = 1;
    if(x[u] && !tag[x[u]]) dfs1(x[u]),siz[u]+=siz[x[u]];
    if(y[u] && !tag[y[u]]) dfs1(y[u]),siz[u]+=siz[y[u]];
}
void dfs2(int u)
{
    if(x[u] && !tag[x[u]])
    {
        if((siz[rt]%2==1 && fa[u] && !tag[fa[u]] && max({siz[x[u]], siz[u]-siz[x[u]], siz[rt]-siz[u]}) <= siz[rt] / 2) || (siz[rt]%2==0 && siz[x[u]]==siz[rt]/2)) p1 = {u,x[u]};
        dfs2(x[u]);
    }
    if(y[u] && !tag[y[u]]) 
    {
        if((siz[rt]%2==1 && fa[u] && !tag[fa[u]] && max({siz[y[u]], siz[u]-siz[y[u]], siz[rt]-siz[u]}) <= siz[rt] / 2) || (siz[rt]%2==0 && siz[y[u]]==siz[rt]/2)) p1 = {u,y[u]};
        dfs2(y[u]);
    }
    if(x[u]&&y[u]&&!tag[x[u]]&&!tag[y[u]])
    {
        if(max({siz[x[u]], siz[y[u]], siz[rt]-siz[x[u]]-siz[y[u]]}) <= siz[rt] / 2) p2 = {x[u],y[u]};
    }
}
void solve()
{
    cin>>n;
    for(int i=1;i<=n;++i)
    {
        tag[i] = 0;
        fa[i] = 0;
    }
    for(int i=1;i<=n;++i) cin>>x[i]>>y[i], fa[x[i]]=fa[y[i]]=i;

    pii bp = make_pair(0,0);
    for(int i=1;i<=n;++i)
    {
        if(!fa[i]) {rt=i; break;}
    }
    while(1)
    {
        dfs1(rt);
        // for(int i=1;i<=n;++i) cout<<siz[i]<<' '; cout<<'\n';
        if(siz[rt]==1) {cout<<"! "<<rt<<'\n'; cout.flush(); return;}
        p1=p2=bp;
        dfs2(rt);
        // cout<<p1.first<<' '<<p1.second<<'\n';
        // cout<<p2.first<<' '<<p2.second<<'\n';
        if(p2!=bp)
        {
            auto [u,v] = p2;
            int t = q(u,v);
            if(t==0) {rt=u; tag[fa[u]]=1;}
            else if(t==2) {rt=v; tag[fa[v]]=1;}
            else tag[u]=tag[v]=1;
        }
        else if(p1!=bp)
        {
            if(siz[rt]%2 == 0) 
            {
                auto [u,v] = p1;
                int t = q(u,v);
                if(t==0) {tag[v]=1;}
                else {rt=v; tag[u]=1;}
            }
            else
            {
                auto [u,v] = p1;
                int w = fa[u];
                // if(v!=x[u]&&x[u]&&!tag[x[u]]) w=x[u];
                // else if(v!=y[u]&&y[u]&&!tag[y[u]]) w=y[u];
                // else if(fa[u]&&!tag[fa[u]]) w=fa[u];
                int t = q(v,w);
                if(t==0) {rt=v; tag[u]=1;}
                else if(t==2) tag[u]=1;   
                else {rt=u; tag[w]=tag[v]=1;}
            }
        }
    }
}
int main()
{
    // ios::sync_with_stdio(false);
    // cin.tie(0);
    int T;
    cin>>T;
    while(T--)
    {
        solve();
    }
    return 0;
}