#include<bits/stdc++.h>
#define ll long long
#define ph push_back
#define rep(i,l,r) for(int i(l),i##end(r);i<=i##end;++i)
#define per(i,r,l) for(int i(r),i##end(l);i>=i##end;--i)
using namespace std;
mt19937 rnd(19937);
const int N=4e5+20; const ll inf=1e18;
int n,de[N],tn,id[N],f[N<<1][17],g[N<<1][17],lg[N<<1],p[N],ans[N]; vector<int> e[N];
void dfs(int u,int fr){
	de[u]=de[fr]+1;
	id[u]=++tn,f[tn][0]=g[tn][0]=u;
	for(int v:e[u]) if(v!=fr){
		dfs(v,u),++tn,f[tn][0]=g[tn][0]=u;
	}
}
int cmp(int i,int j){
	return de[i]<de[j]?i:j;
}
int dis(int x,int y){
	x=id[x],y=id[y]; if(x>y) swap(x,y);
//	printf("%d %d %d   %d %d  %d\n",x,f[x][0],f[x][lg[y-x+1]],y,f[y][0],g[y][lg[y-x+1]]);
	return de[f[x][0]]+de[f[y][0]]-2*de[cmp(f[x][lg[y-x+1]],g[y][lg[y-x+1]])];
}
void solve(){
	rep(i,1,n) e[i].clear();
	int s,t; 
	scanf("%d%d%d",&n,&s,&t);
	rep(i,2,n) {
		int u,v;
		scanf("%d%d",&u,&v);
		e[u].ph(v),e[v].ph(u);
	}
	tn=0,dfs(1,0);
//	rep(i,1,tn) printf("%d ",f[i][0]); puts("");
	rep(i,2,tn) lg[i]=lg[i>>1]+1;
	//tn=2n <= 1e5 < 2^17
	rep(j,1,16) rep(i,1,tn) {
		if(i+(1<<j-1)<=tn) f[i][j]=cmp(f[i+(1<<j-1)][j-1],f[i][j-1]);//<=tn!!!
		if(i-(1<<j-1)>=1) g[i][j]=cmp(g[i-(1<<j-1)][j-1],g[i][j-1]);
	}
//	rep(i,1,n) rep(j,i+1,n) printf("%d %d  %d\n",i,j,dis(i,j));
	rep(i,1,n) p[i]=i;
	p[s]=1,p[t]=n,p[1]=s,p[n]=t;
	
	int kw,w=0;
	rep(i,2,n) w^=dis(p[i-1],p[i]);
	kw=w; rep(i,1,n) ans[i]=p[i];
	
	if(n<=3) return ;
	
	rep(T,1,50*n){
		//[2,n-1]
		int x=rnd()%(n-2)+2,y=rnd()%(n-3)+2;
		if(y==x) y++;
		w^=dis(p[x-1],p[x])^dis(p[x],p[x+1])^dis(p[y-1],p[y])^dis(p[y],p[y+1]);
		swap(p[x],p[y]);
		w^=dis(p[x-1],p[x])^dis(p[x],p[x+1])^dis(p[y-1],p[y])^dis(p[y],p[y+1]);
		
		if(w<kw){
			kw=w; rep(i,1,n) ans[i]=p[i];
		}
	}
	cerr<<kw<<'\n';
}
signed main(){
	int T; scanf("%d",&T);
	while(T--){
		solve();
		rep(i,1,n) printf("%d ",ans[i]); puts("");
//		rep(i,2,n) printf("%d\n",dis(ans[i-1],ans[i])); puts("\n");
	}
	return 0;
}