#include<bits/stdc++.h>
#define int long long
#define ull unsigned long long
#define repe(i,l,r) for(int (i)=l;(i)<=r;(i)++)
#define rep(i,n) for(int (i)=1;(i)<=n;(i)++)
#define FOR(i,r,l) for(int (i)=r;(i)>=l;(i)--)
#define INF 0x3f3f3f
#define pii pair<int,int>
#define mpr make_pair
#define pb push_back
#define ALL(v) (v).begin(),(v).end()
#define rsort(v) sort(ALL(v),greater<int>())
#define lb(v,x) (int)(lower_bound(ALL(v),x)-v.begin())
#define ub(v,x) (int)(upper_bound(ALL(v),x)-v.begin())
#define uni(v) v.resize(unique(ALL(v))-v.begin())
using namespace std;
int read(){int sum=0,f=1;char c;c=getchar();while(c<'0'||c>'9'){if(c=='-')f=-1;c=getchar();}while(c>='0'&&c<='9'){sum=(sum<<1)+(sum<<3)+(c-'0');c=getchar();}return sum*f;}
void out(int x){if(x<0){x=-x;putchar('-');}if(x>=10)out(x/10);putchar(x%10+'0');}
template <typename T>void die(T s){cout<<s<<endl;exit(0);}
int fast(int a,int b,int P){int res=1;if(P<=0){while(b){if(b&1)res=res*a;a=a*a;b>>=1;}}else{while(b){if(b&1)res=res*a%P;a=a*a%P;b>>=1;}}return res;}
template <typename T>void chkmax(T& a,T b){if(a<b)a=b;return;}
template <typename T>void chkmin(T& a,T b){if(a>b)a=b;return;}
int n,s,t;
const int N=5e4+5;
vector<int> G[N];
namespace LCA{
    int dfn[N],mi[21][N],cnt,dep[N];
    int get(int x,int y){return dfn[x]<dfn[y]? x:y;}
    void dfs(int u,int fa){
        mi[0][dfn[u]=++cnt]=fa;
        dep[u]=dep[fa]+1;
        for(auto v:G[u]){
            if(v==fa)continue;
            dfs(v,u);
        }
        return;
    }
    void init(){
        cnt=0;
        dfs(1,0);
        //cerr<<mi[0][2]<<' '<<dfn[2]<<endl;
        for(int j=1;(1<<j)<=n;j++){
            for(int i=1;i+(1<<j)-1<=n;i++){
                mi[j][i]=get(mi[j-1][i],mi[j-1][i+(1<<j-1)]);
            }
        }
    }
    int lca(int u,int v){
        if(u==v)return u;
        u=dfn[u],v=dfn[v];
        if(u>v)swap(u,v);
        int len=__lg(v-u++);
        return get(mi[len][u],mi[len][v-(1<<len)+1]);
    }
    int dis(int u,int v){
        return dep[u]+dep[v]-dep[lca(u,v)]*2;
    }
}
using namespace LCA;
bool all(){
    rep(i,n)if(G[i].size()==n-1)return true;
    return false;
}
int p[N];
int nd[N],ans;
mt19937_64 rnd(time(0));
int rd(int l,int r){
    return rnd()%(r-l+1)+l;
}
int calc(){
    int res=0;
    rep(i,n-1){
        res^=dis(p[i],p[i+1]);
    }
    return res;
}
void solve(){
    n=read(),s=read(),t=read();
    rep(i,n)G[i].clear();
    rep(i,n-1){
        int u=read(),v=read();
        G[u].pb(v);
        G[v].pb(u);
    }
    LCA::init();
    p[1]=s,p[n]=t;
    repe(i,1,n)if(i!=s&&i!=t)p[i-(i>s)-(i>t)+1]=i;
    if(all()){
        rep(i,n)cout<<p[i]<<' ';
        puts("");
        return;
    }
    else if(n<=9){
        ans=10;
        //cerr<<lca(1,5)<<endl;
        do{
            int res=0;
            for(int i=1;i<n;i++){
                res^=dis(p[i],p[i+1]);
            }
            //cerr<<res<<endl;
            if(res<ans){
                rep(i,n)nd[i]=p[i];
                ans=res;
            }
        }while(next_permutation(p+2,p+n));
        //cerr<<ans<<endl;
        rep(i,n)cout<<nd[i]<<' ';
        puts("");
        return;
    }
    else{
        ans=calc();
        for(;ans>1;){
            int l=rd(2,n-2),r=rd(l+1,n-1);
            ans^=dis(p[l],p[l+1])^dis(p[r-1],p[r])^dis(p[l-1],p[l])^dis(p[r],p[r+1]);
            swap(p[l],p[r]);
            ans^=dis(p[l],p[l+1])^dis(p[r-1],p[r])^dis(p[l-1],p[l])^dis(p[r],p[r+1]);
        }
        out(ans);
    }
    return;
}
signed main(){
    int T=read();
    while(T--)solve();
    return 0;
}