#include <bits/stdc++.h>
	#define REP(i, first, last) for (int i = (first); i <= (last); ++i)
	#define DOW(i, first, last) for (int i = (first); i >= (last); --i)
	using namespace std;
	// #define int long long
	#define pb emplace_back
	#define ull unsigned long long
	const int N = 5e5 + 5, M = 2e5 + 5, Sg = 26;
	const int mod1 = 1e9 + 9, mod2 = 998244353;
	const long long inf = 1e18;
	const int dx[] = {-1, -1, -1, 0, 0, 0, 1, 1, 1};
	const int dy[] = {-1, 0, 1, -1, 0, 1, -1, 0, 1};
	const int P = 1ll << 21, S = P - 1;
	struct Graph {
	  struct edge {
	    int from, to, next;
	    int w;
	  } e[N << 1];
	  int cnt, n, head[N];
	  void ins(int u, int v, int w = 0) {
	    e[++cnt] = {u, v, head[u], w}, n = max({n, u, v}), head[u] = cnt;
	  }
	  void twi(int u, int v, int w = 0) { ins(u, v, w), ins(v, u, w); }
	  void clear() {
	    for (int i = 1; i <= cnt; i++) head[e[i].from] = 0;
	    cnt = 0;
	  }
	#define FEG(u, v, W, G, i)                                \
	  for (int i = G.head[u], v = G.e[i].to, W = G.e[i].w; i; \
	       i = G.e[i].next, v = G.e[i].to, W = G.e[i].w)
	} G;
	int n, s, t;
	int pos[N];
	struct LCA {
	  int dfn[N], dfncnt = 0, pre[N], siz[N], f[N][25], dep[N];
	  void dfs(int u, int fa) {
	    dfn[u] = ++dfncnt;
	    dep[u] = dep[fa] + 1;
	    pre[dfncnt] = u;
	    f[u][0] = fa;
	    REP(i, 1, 20) f[u][i] = f[f[u][i - 1]][i - 1];
	    FEG(u, v, W, G, i) {
	      if (v == fa) continue;
	      dfs(v, u);
	      pre[++dfncnt] = u;
	    }
	  }
	  int logn[N << 1];
	  int st[N << 1][25];
	  void init() {
	    logn[0] = -1;
	    REP(i, 1, dfncnt) {
	      logn[i] = logn[i / 2] + 1;
	      st[i][0] = pre[i];
	    }
	    for (int j = 1; (1 << j) <= dfncnt; j++) {
	      for (int i = 1; i + (1 << j) <= dfncnt + 1; i++) {
	        int u = st[i][j - 1], v = st[i + (1 << (j - 1))][j - 1];
	        st[i][j] = ((dep[u] > dep[v]) ? v : u);
	      }
	    }
	  }
	  int lca(int l, int r) {
	    int ql = dfn[l], qr = dfn[r];
	    if (qr < ql) swap(qr, ql);
	    int k = logn[qr - ql + 1];
	    return (dep[st[ql][k]] < dep[st[qr - (1 << k) + 1][k]]
	                ? st[ql][k]
	                : st[qr - (1 << k) + 1][k]);
	  }
	  int dist(int u, int v) {
	    int w = lca(u, v);
	    return dep[u] + dep[v] - 2 * dep[w];
	  }
	} f;
	bool check() {
		REP(u, 1, n) {
			int ans = 0;
			FEG(u, v, w, G, i) {
				ans ++;
			}
			if(ans == n - 1) return 1;
		}
		return 0;
	}
	mt19937_64 rnd(chrono :: system_clock().now().time_since_epoch().count());
	int rand(int l, int r) {
		return rnd() % (r - l + 1) + l;
	}
	int get(int x) {
		return f.dist(pos[x], pos[x - 1]) ^ f.dist(pos[x], pos[x + 1]);
	}
	bool vis[N];
	int ans = 1e9, opt[N];
	void answer() {
		int res = 0;
		REP(i, 1, n - 1) res ^= f.dist(pos[i], pos[i + 1]);
		// cerr << res << ' ' << ans << '\n';
		if(res < ans) {
			ans = res;
			REP(i, 1, n) opt[i] = pos[i];
		}
	}
	void dfs(int u) {
		if(u >= n) return answer();
		REP(i, 1, n) {
			if(vis[i] || f.dist(i, pos[u - 1]) > 4) continue;
			pos[u] = i, vis[i] = 1;
			dfs(u + 1), vis[i] = 0;
		}
	}
	void Solve() {
	  cin >> n >> s >> t;
	  // cerr << "qwq";
	  G.clear(), f.dfncnt = 0;
	  REP(i, 2, n) {
	    int u, v;
	    cin >> u >> v;
	    G.twi(u, v);
	  }
	  pos[1] = s, pos[n] = t;
	  int l = 1;
	  REP(i, 2, n - 1) {
	    while (l == s || l == t) l++;
	    pos[i] = l, l ++;
	  }
	  // REP(i, 1, n) cerr << pos[i] << ' ';
	  // cerr << '\n';
	  f.dfs(1, 0), f.init();
	  int res = 0;
	  REP(i, 1, n - 1) res ^= f.dist(pos[i], pos[i + 1]);
	  if(check()) {
	  	REP(i, 1, n) cout << pos[i] << ' ';
	  	cout << '\n';
	  	return ;
	  }
	  if(n < 9) {
	  	REP(i, 1, n) vis[i] = 0;
	  	vis[s] = vis[t] = 1;
	  	ans = 1e9, dfs(2);
	  	REP(i, 1, n) cout << opt[i] << ' ';
	  	cout << '\n';
	  	return ;
	  }
	  while(res > 1) {
	  	int x = rand(2, n - 1), y = rand(2, n - 1);
	  	while(x == y) y = rand(2, n - 1);
	  	res ^= get(x) ^ get(y);
	  	swap(pos[x], pos[y]);
	  	res ^= get(x) ^ get(y);
	  }
	  REP(i, 1, n) cout << pos[i] << ' ';
	  cout << '\n';
	}
	signed main() {
	  //	freopen(".in", "r", stdin);
	  //	freopen(".out", "w", stdout);
	  ios::sync_with_stdio(false);
	  cin.tie(nullptr), cout.tie(nullptr);
	  int T = 1;
	  cin >> T;
	  while (T--) {
	    Solve();
	  }
	  return 0;
	}