#include<iostream>
#include<cstdio>
#include<vector>
#include<cstdlib>
#include<random>
#include<algorithm>
#define N 500000
#define M 1000000
using namespace std;
mt19937 RAND(random_device{}());
int read()
{
	char c=0;
	int sum=0;
	while (c<'0'||c>'9') c=getchar();
	while ('0'<=c&&c<='9') sum=sum*10+c-'0',c=getchar();
	return sum;
}
int T,n,s,t,length,lg[M+1],depth[N+1],dfn[N+1],rev[N+1],ps[N+1],tong[N+1],leng,ST[M+1][21],p[N+1],tans;
vector<int>E[N+1];
bool used[N+1];
void add(int x,int y)
{
	E[x].push_back(y),E[y].push_back(x);
	return;
}
void dfs(int x)
{
	dfn[x]=++leng,rev[dfn[x]]=x,used[x]=1,tong[++length]=dfn[x],ps[x]=length;
	for (int i=0;i<E[x].size();++i)
		if (!used[E[x][i]])
			depth[E[x][i]]=depth[x]+1,dfs(E[x][i]),tong[++length]=dfn[x];
	return;
}
int lca(int x,int y)
{
	x=ps[x],y=ps[y];
	if (x>y) swap(x,y);
	int lw=lg[y-x+1];
	return rev[min(ST[x][lw],ST[y-(1<<lw)+1][lw])];
}
int dis(int x,int y)
{
	return depth[x]+depth[y]-(depth[lca(x,y)]<<1);
}
int main()
{
	int x,y,ps,res;
	bool op,opt;
	for (int i=2;i<=M;++i) lg[i]=lg[i>>1]+1;
	T=read();
	while (T--)
	{
		n=read(),s=read(),t=read(),leng=length=opt=0;
		for (int i=1;i<=n;++i) E[i].clear(),used[i]=0;
		for (int i=1;i<=n-1;++i) x=read(),y=read(),add(x,y);
		for (int i=1;i<=n;++i)
			if (E[i].size()==n-1)
				opt=1;
		depth[1]=1,dfs(1);
		for (int i=1;i<=length;++i) ST[i][0]=tong[i];
		for (int i=1;i<=lg[length];++i)
			for (int j=1;j+(1<<i)-1<=length;++j)
				ST[j][i]=min(ST[j][i-1],ST[j+(1<<(i-1))][i-1]);
		p[1]=s,p[n]=t,ps=1;
		for (int i=2;i<=n-1;++i)
		{
			while (ps==s||ps==t) ps++;
			p[i]=ps,ps++;
		}
		if (n>4)
		{
			op=dis(s,t)&1,shuffle(p+2,p+n,RAND),res=0;
			if (opt)
			{
				for (int i=1;i<=n;++i) printf("%d ",p[i]);
				puts("");
				continue;
			}
			for (int i=1;i<=n-1;++i) res^=dis(p[i],p[i+1]);
			while (1)
			{
				x=RAND()%(n-3)+2,res^=dis(p[x-1],p[x])^dis(p[x-1],p[x+1])^dis(p[x+2],p[x+1])^dis(p[x+2],p[x]),swap(p[x],p[x+1]);
				if (res==op) break;
			}
			for (int i=1;i<=n;++i) printf("%d ",p[i]);
			puts("");
		}
		else if (n==4)
		{
			if ((dis(p[1],p[3])^dis(p[2],p[3])^dis(p[2],p[4]))<(dis(p[1],p[2])^dis(p[2],p[3])^dis(p[3],p[4]))) swap(p[2],p[3]);
			for (int i=1;i<=n;++i) printf("%d ",p[i]);
			puts("");
		}
		else
		{
			for (int i=1;i<=n;++i) printf("%d ",p[i]);
			puts("");
		}
	}
	return 0;
}