#include <bits/stdc++.h>
#ifdef zhr_debug
#define debug printf
#endif
#ifndef zhr_debug
void debug(const char* s,...){}
#endif
using namespace std;
inline int randrange(int l,int r){return (rand()<<15|rand())%(r-l+1)+l;}
void freopen(string file){freopen((file+".in").c_str(),"r",stdin);freopen((file+".out").c_str(),"w",stdout);}
int n,s,t;
vector<int> e[50020];
int dep[50020];
int sz[50020];
int son[50020];
int top[50020];
int fa[50020];
void dfs1(int x,int f)
{
	fa[x]=f;
	sz[x]=1;
	dep[x]=dep[f]+1;
	for(int v:e[x])
	{
		if(v==f) continue;
		dfs1(v,x);
		sz[x]+=sz[v];
		if(sz[v]>sz[son[x]]) son[x]=v;
	}
}
void dfs2(int x,int f,int tp)
{
	top[x]=tp;
	if(son[x]) dfs2(son[x],x,tp);
	for(int v:e[x])
	{
		if(v==f || v==son[x]) continue;
		dfs2(v,x,v);
	}
}
int getlca(int x,int y)
{
	while(top[x]^top[y])
	{
		if(dep[top[x]]<dep[top[y]]) swap(x,y);
		x=fa[top[x]];
	}
	return dep[x]<dep[y] ? x : y;
}
inline int getdis(int x,int y){return dep[x]+dep[y]-2*dep[getlca(x,y)];}
void initialize()
{
	for(int i=1;i<=n;i++) e[i].clear();
	fill(son,son+n+1,0);
}
int a[50020];
namespace __Sub1
{
	int dis[15][15];
	int ans[50020];
	int mn,cur;
	void solve()
	{
		for(int i=1;i<=n;i++)
		{
			for(int j=1;j<=n;j++)
			{
				dis[i][j]=getdis(i,j);
			}
		}
		mn=0x3f3f3f3f;
		do
		{
			cur=0;
			for(int i=1;i<n;i++) cur^=dis[a[i]][a[i+1]];
			if(cur<mn)
			{
				mn=cur;
				for(int i=1;i<=n;i++) ans[i]=a[i];
			}
		}
		while(next_permutation(a+2,a+n));
		for(int i=1;i<=n;i++) printf("%d ",ans[i]);printf("\n");
	}
}
bool flower()
{
	for(int i=1;i<=n;i++) if(e[i].size()==n-1) return true;
	return false;
}
int calc(int x)
{
	return getdis(a[x-1],a[x])^getdis(a[x],a[x+1]);
}
void solve()
{
	cin>>n>>s>>t;
	initialize();
	for(int i=1,x,y;i<n;i++)
	{
		scanf("%d%d",&x,&y);
		e[x].push_back(y);
		e[y].push_back(x);
	}
	dfs1(1,0);
	dfs2(1,0,1);
	a[1]=s;a[n]=t;
	for(int i=1,p=1;i<=n;i++)
	{
		if(i==s || i==t) continue;
		a[++p]=i;
	}
	if(n<=9)
	{
		__Sub1::solve();
		return;
	}
	if(flower())
	{
		for(int i=1;i<=n;i++) printf("%d ",a[i]);printf("\n");
		return;
	}
	int cur=0;
	for(int i=1;i<n;i++) cur^=getdis(a[i],a[i+1]);
	while(cur>1)
	{
		int x=randrange(2,n-1),y=randrange(2,n-1);
		while(x==y) y=randrange(2,n-1);
		cur^=calc(x)^calc(y);
		swap(a[x],a[y]);
		cur^=calc(x)^calc(y);
	}
	for(int i=1;i<=n;i++) printf("%d ",a[i]);printf("\n");
}
int main()
{
	srand(time(0));
	int t;
	cin>>t;
	while(t--) solve();
	return 0;
}